Georgian Court University
Our Own Estuary: The Barnegat Bay
The Barnegat Bay watershed lies wholly within a physiographic region known as the Atlantic Coastal Plain. This plain is characterized by a flat or gently rolling topography that rises gradually from sea level to a maximum of 800 feet on its western edge and by broad, slowly-flowing rivers and streams. The relatively flat nature of the plain, the abundant streams and occasional clay-lined depressions mean that, many areas support areas of standing water where white cedar and hardwood swamps may form. These damp, swampy forests are in sharp contrast to the dry sandy pine-barrens and coastal dunes to the East.
The Barnegat Bay Estuarine System itself is located along the central shore of New Jersey and is bordered throughout by Ocean County. The system is about 70km miles long but is a relatively narrow (2-6km), shallow, lagoonal estuary, which is divided into three main subsystems: Barnegat Bay, Manahawkin Bay and Little Egg Harbor. (Manahawkin Bay is contiguous with Barnegat Bay, with only the Route 72 bridge dividing the two... so many papers treat Manahawkin as part of the larger Barnegat Bay). With a maximum depth of about 23 feet in some areas, Little Egg Harbor is a deeper estuary than Barnegat Bay. Overall the depth of the Barnegat Bay Estuarine System ranges from 1 to 6m (in the dredged channel) with an average depth of about 1.5m. Depending on which estimate you believe the Watershed of the Bay is somewhere between 550 and 660 square miles (ca 1,730 square km). A barrier island, Long Beach Island (LBI) and a barrier peninsula bound the Bay on the east. The southern half of the northern peninsula is an undeveloped area, Island Beach State Park, while the southern island consists of the heavily developed beach communities of LBI. The Bay's western boundary is a patchwork of residential developments interspersed with undeveloped salt marshes of the Forsythe Wildlife Refuge. In addition, the western coast of the bay is broken by a series of fresh surface-water inputs including the Metedeconk River, Kettle Creek, Toms River, Cedar Creek, Forked River, Mill Creek, West Creek, and Tuckerton Creek. Because these inputs are often influenced by the tannic inputs from the Cedar swamps the water of the Barnegat Bay often has a brownish coloration, especially after strong storm events.
The Bay's main connection to the Atlantic Ocean is through the Barnegat Inlet, which has recently been the target of a large-scale reconfiguration (redirection of flows by dredging and filling) by The United States Army Corps of Engineers. The full impact of this project on the circulation and flushing patterns of the estuarine system are only now being examined. However, this is far from the first time that the flow patterns into and out of the Bay have been reorganized. For example, from historical charts it can be ascertained that, a hundred years ago, Barnegat Inlet opened about a mile north of its present position. Similar comparisons made at Holgate show that the inlet there has opened and closed several times since the turn of the century. The limited flow through the Bay's inlets reduces the amount of water flushing into and out of the estuary, making this system particularly susceptible to impacts of human activities within the watershed.
Originally, there was no access to the ocean at the Northern End of the Bay. However, in 1926 the Point Pleasant Canal was opened, linking Bay Head to the Manasquan River. The canal allowed vessels to enter the Bay via Manasquan Inlet, and took 20 miles of ocean sailing off a trip up the coast. However, within months of the canal's opening, shifting sands closed off Manasquan Inlet and ocean access to the Northern Portion of the Bay was once more impossible. It took almost 5 years (until 1931) for the Army Corps of Engineers to dredge a new entrance to Manasquan Inlet and to protect its entrance using Jetties made from rocks removed from under New York city during the construction of the city's subway system. The restricted flow through inlets means that Barnegat Bay has a tidal range of less than a foot. Thus tidal differences between tidal Manasquan and the Bay (the two ends of the canal) can be as much as four feet, causing swift currents (up to 9 knots) and turbulent waters within the Canal during times of maximal flow. Surprisingly, though, there does not appear to be a substantial inter-change of fresh and saltwater between the Bay and River through this canal.
Early History of the Region
The original inhabitants of the Barnegat region were the Lenni Lenape Indians. Piles of oyster, clam and mussel shells found in Tuckerton and Brigantine dating from before European settlement suggest that that shellfish were important parts of the Lenape's diet. Other remains suggest use of local birds and their eggs, muskrat, bear, deer, otter, beaver, and lynx. The Lenape also made use of local plants. For example, the Indians used the wood from the locally abundant Cedar trees for cooking and for bowls, as well as harvesting the wild cranberries, blackberries, strawberries and "whortleberries" (whatever those are!). In addition, the Lenape cultivated corn, potatoes, peanuts, tobacco, beans and squash. Indeed, it has been suggested that it was they who pioneered the use of seaweed for fertilizer, although I suspect that this discovery was actually made numerous times by farmers in coastal regions around the world!
The first European to explore the Barnegat Bay was Henry Hudson who anchored off Barnegat Inlet in 1609 explored the region in longboats. The area was further mapped by Cornelius Jacobson Mey in 1614. Two of the local place names that derived from Mey's maps of the region are Barende-gat (Inlet of breakers), now Barnegat, and Eyre Haven (Egg Harbor). The latter got its name because early Dutch explorers found many nests filled with the eggs of seabirds in the area, and Eyren Haven means Harbor of Eggs. For almost a century after that the area was visited mostly by nomadic fishermen, whalers attracted by seasonal whale runs within sight of land) and pirates. The latter reportedly visited the area to bury treasure: Spanish silver coins are still occasionally recovered along the beaches of Long Beach Island and there is at least one well-authenticated instance of a significant find of treasure made on LBI in the late 1800's.
However permanent settlement slowly took place. In the early 1700s, the whaler Aaron Inman, built a home near what is now Surf City (LBI) and, in 1704, Edward Andrews built the first gristmill on the Jersey coast using water from a beaver pond to power his mill. The first settlers, many of whom were squatters with no legal right to the land they settled, supplemented their incomes by salvaging and smuggling, as well as by fishing and crabbing and harvesting salt-hay. Oysters rapidly became a major export from Barnegat Bay, and regulation came early. In 1719 a law was passed that forbade gathering oysters in the Bay from May 10 to September 1. This law may have helped maintain the oyster fishery, which was a major part of the economics of the region for the next two centuries. By the 1760s numerous sawmills had sprung up along the numerous Creeks of Ocean County, and Toms River became an important port town, with fish being transported from there to Mount Holly and Philadelphia, while exports left there for many international destinations. This was because, at the time there was a relatively deep (15') channel through Cranberry Inlet, directly opposite Toms River. This channel was deep enough to allow passage of two and three-masted schooners into the upper Barnegat Bay until, in 1812, a violent storm closed the inlet. Hunting was also common in the region.
During the Revolutionary War the protected coves and inlets of the Barnegat Bay provided shelter to a number of the small privateers used by the US forces harass and capture British. In addition, because coastal areas like the Barnegat were a source of the salt needed to preserve food, local confrontations occurred as the two forces vied for control of productive salt-works. Not all members of the local communities supported the nationalist cause, and a number of loyalists lived (and died) in the region during this time.
After the war the relative abundance of lumber and the accessibility to water meant that boat and shipbuilding became major industries in the Barnegat region during the 19th century. For example, 1830s the Barnegat Bay "Sneakbox" a small, shallow draft, broad-beamed sailing boat designed to be easily poled up into the reeds and camouflaged was introduced for used as a duck blind. However the design was so popular that it was adapted and produced in a variety of sizes for different uses.
As shipping increased in importance in the region, the problems of navigation in the ever-changing channels of the Barnegat and the severity of the storms that battered the region began to take their toll. Between 1830 and 1837 more than 125 vessels wrecked and sank between Point Pleasant and Barnegat Inlet and in the spring of 1854 seven ships were wrecked within 13 days of one another. The worst lost of life in a single wreck occurred when the Powhatan, a ship packed with immigrants, foundered off the coast of Long Beach Island, with the loss of over 350 lives. As a result, the area became dubbed "The Graveyard of the Atlantic". In response the government erected what were termed "houses of refuge" with equipment for rescuing and sheltering shipwreck survivors. The first of these, Phillips Station #14 on Long Beach Island, was erected at the turn of the Century. In 1849, it was replaced and the name changed to the Island Beach Life Saving Station #14 and in 1915 all these stations became the United States Coast Guard stations. In addition, in 1935, a lighthouse was built on the Northern Tip of Barnegat Inlet, which was replaced in 1858 with the much taller (172 feet) lighthouse you see today ("Barney"), built on the same site which was active until 1944.
In February 15, 1850 the portion of Monmouth County south of the Manasquan River was designated as a new county, called Ocean County, by an act of the state legislature.
During the early 1800s the charcoal industry drove much deforestation in the Barnegat watershed. This in turn left many swampy areas that were useless for anything but the cultivation of cranberries starting in the 1850s. Around 1863 the Cranberry industry suddenly started to expand the area, and cranberries rapidly became a hot property item. Anyone who had (or could borrow) money bought up swamp-land and started to grow cranberries. The price of swampland went through the roof, and even pine-barrens brought a hundred dollars an acre (a princely sum at the time). Of course, all these extra acres of cranberries rapidly resulted in a glut of the fruit, prices fell and most of the entrepreneurs went bankrupt. Thus, by the early 1900s the bogs and woodlands had mainly returned to wild places, supporting the next wave of land use... hunting and sport's fishing. Reports from this time emphasize the abundance of birds, with hundreds often being shot in a day by a single hunter. The fishing was also reportedly excellent, with shad, sturgeon, and crab fishing complementing the shellfish industry.
During WWI, the town of Tuckerton became famous when it was discovered that the Germans had built an 820 foot high radio tower on Mystic Island. The tower was seized and used by the US for the remainder of the war.
During the 1960s and 70s, Ocean County became the fastest-growing county in the U.S. with a high proportion of the new residents being senior citizens. The County currently has the greatest highest concentration of retirement communities of any County in the Northeast.
Wildlife of the Barnegat Bay Region
The Barnegat Bay system is home to an abundance of wildlife:
New Jersey has nineteen species federally-listed as threatened or endangered. Among the endangered plants found in the Barnegat region are American chafseed, Knieskern's beaked-rush, sensitive joint-vetch and swamp pink. The Bay system also provides important habitat for several endangered animal species, including the least tern, roseate tern, piping plover, bald eagle, peregrine falcon and the threatened Ipswich sparrow. The diamondback terrapin, a candidate for federal protection, also uses the Bay area for breeding grounds. And of course there's also the Jersey Devil... J
Human Uses of the Barnegat Bay Watershed
Management Issues in Estuaries
Most problems in estuarine management involve conflict between increasing human populations, and the “natural” system. These conflicts require creation and policing of policies for estuarine use. The biggest issues for management of estuaries currently are pollution, changes in discharge patterns of tributaries and use of wildlife (especially fisheries).
We have already seen that nutrients have a profound effect on estuarine ecosystems. From a management point of view, nutrient inputs are often divided into point versus non-point nutrient discharge. Point sources are those sources where a very localized input contributes significant amounts of nutrient (unregulated sewage plant outfall), whereas non-point sources are broadly distributed, often individually lower-leveled inputs of nutrients (runoff from agriculture for example). Early regulation targeted point sources and was fairly successful in creating marked reductions in nutrient inputs from point sources However, non-point sources have been much harder to control, partially because so many individuals are involved, and partially due to resistance from those being regulated (farmers, gardeners etc).
Nutrient Status of the Barnegat Bay: The National Estuarine Eutrophication Assessment 2008 suggested the Bay was in pretty bad shape, falling in the highest category for nutrient pollution: Highly eutrophied. Nutrients, such as nitrogen and phosphorus, are introduced to the estuary by urban stormwater, sewage treatment plants, atmospheric deposition, and boater discharges. Over 450,000 people live within the Barnegat Bay watershed and that number more than doubles in the summer as people flock to the shore. Nitrogen loads to the water shed have been shown to have increased from 441 metric tons per year in 1972 to 454 metric tons in the late 80s, with more than 75% of these inputs being associated with non-point source pollution (particularly fertilizers and pesticides from domestic lawns and golf courses). The resulting eutrophication stimulates algal growth and thus limits the extent of eelgrass beds in the Bay. Decomposition of the algal biomass in the warm Bay waters may cause hypoxia or anoxia, even in the relatively shallow waters of the system. Nitrogen budgets for the Bay suggest that DIN inputs from surface water are 118mmol N/m2/yr (ca 50%) and from ground water are 13mmolN/m2/yr (11%). Another 100mmol/m2/yr (39%) come from atmospheric N, marinas contribute ca. 10 and boats another 1. Nitrogen inputs are larger from the Northern Estuary than those in the South. However, once in the Bay, organic nitrogen comprises 87-90% of the total N present. Bottom sediments are a major N-sink, but the largest removal of N from the system (ca 70%) comes from export to the ocean.
Probably also as a result of nutrient loading, since the mid-1980s intense summer blooms of picoplanktonic algae, dominated by the non-motile chlorophye algae, Nannochloris atomus, with highest cell counts (over 3 million cells / ml) have occurred, especially in the South part of the estuary. In addition, blooms of the "brown tide" organism Aureococcus anophagefferens, have been observed every summer from 1995 to the present, esp. in Little Egg Harbor. While the bloom’s initiation appears linked to nutrient levels, its end seems to be linked to a virus specific to Aureococcus anophagefferens. At the bloom’s inception few algae appear to be infected by this virus whereas, toward the bloom infection levels near 50% suggesting that lysis caused by the virus may be the main mechanism for ending the bloom. The increase in brown tides has been linked to reductions in the population size of juvenile hard clam (Mercinaria mercinaria) populations in region since these animals will stop filtering when Aureococcus anophagefferens is present in the water column, and smaller clams may starve to death during the bloom as a result. Stocks of juvenile hard clams in Little Egg Harbor decreased by two-thirds between 1986 and 2001. Brown-tide occurrence also appears to be related to development and spread of ‘wasting disease’ Z. marina. It appears that the added light stress created by the brown tides allows spread of disease among seagrass populations.
Macroalgal blooms also appear to be related to eutrophication. Accelerated growth of drifting macroalgae (e.g. Ulva lactuca, Agardhiella subulata, Ceramium spp., and Gracilaria tikvahiae) in response to elevated nutrient levels produces extensive organic mats that outcompete seagrasses for light. In addition, decomposition of thick macroalgal mats can promote sulfide accumulation and development of hypoxic/anoxic conditions in bottom sediments that are devastating to benthic infaunal communities.
Eutrophication has also been linked to recent increases in jellyfish populations within the Bay. Before 2000 sea nettles were not common in Barnegat. However, between 2000 and 2006 periodic sea nettle blooms occurred especially in low salinity areas, with particularly high numbers being observed in 2004. While eutrophication is almost certainly part of the story of the recent jelly fish blooms, global warming also be aiding the northward expansion of jellyfish blooms in U.S. estuaries since sea nettles thrive at temperatures above 25 ºC
Addition of organic materials can be associated with sewage or fecal inputs loading of the system. Other sources of organic materials include pulp and paper mills, and other lumber-associated industries (many of which also input Chlorine and other toxicants as well) and aquaculture operations, such as intensive culture of fin-fish or shellfish like mussels. Organic material produced by all these sources can directly choke benthic systems, by coating the organisms there and can also decrease oxygen levels in the system by increasing BOD. However, since sewage is now routed under the Barnegat Bay and into the ocean and pulp and paper industries and aquaculture are not major factors in the watershed (a few small clam hatcheries not withstanding), this is not a major factor in the watershed today.
Changes in volume or timing of freshwater inputs
Changes in the volume or timing of freshwater inputs to estuaries may have several causes. As we have seen, changes in the pattern of precipitation (rain versus snow) change timing of periods of maximal flow can occur naturally and are currently being exacerbated by global warming. In addition, human interventions, such as diversion of river flows for irrigation, industrial use and even bottling can decrease the amount of fresh water reaching estuaries, with potentially important consequences for stratification and osmotic gradients within the estuary. Increased use of both surface water and groundwater are also strongly impacting many estuaries, especially when sewage plants do not recycle treated waste-waters back into the same drainage basin. For example, many in NJ pump wastes into the ocean, which saves the estuaries from potentially destructive pollutants, but removes a significant amount of the normal freshwater flow from the estuary. Freshwater withdrawals from surface and groundwater sources in Ocean County increased from 56 million gallons per day in 1985 to 71 million gallons in 2000 with 70% of withdrawn water being used for public water supplies. The amount of water removed from the watershed through sewerage outfall to ocean averages 60 million gallons per day in summer which is equivalent to 1/3 freshwater inflow to estuary under extreme low flow conditions. As a consequence significant drops have been noted in stream levels within the watershed during dry summers, and the penetration of high salinity water in the estuary has moved landward measurably in recent decades.
Another factor that affects estuarine flows is damming of the fresh water inputs (for reservoir or hydroelectric purposes). Such activities not only change water flow patterns, but also often strongly effect sediment input rates (sediments fall out behind the dam) and thus nutrient dynamics (many nutrients are attached to sediments, others may be stripped by blooms in the newly created water body). Many ofciated with heavy rainfall, preventing storm surges and integrating water supply to the estuary over an annual cycle. As humans develop a watershed, the portion of impervious substrates increases. Consequently the pattern of wate the rivers entering the Bay are dammed (e.g. Metedeconk dam which is dammed to form Lake Carasaljo and, more recently, Brick Reservoir).
A third and perhaps less obvious way in which water flow patterns can be changed comes from the covering of normal soil by impervious substrates, like roads, buildings and parking lots. When rain falls on healthy soil, much of the water sinks in and flows downhill slowly, slowed by the convoluted route it must take between soil grains. Thus natural soils and marshes act as buffers, evening out flows asso r delivery to the estuary becomes more episodic, increasing the potential for osmotic stresses as well as the tendency of associated constituents (nutrients, toxic chemicals) to be delivered in pulses that are harder for the estuary to process without damage to its components. The sandy soils of the areas surrounding the Barnegat Bay mean that this region has a naturally tight linkage between shallow ground water quality and open water quality. However, as mentioned earlier, increasing population density in the Barnegat region has resulted in the watershed becoming increasingly developed and urbanized. As a result many of the wetlands, forests and other natural areas have been covered by impervious surfaces, such as roofs and pavement. An average of 20% of watershed's riparian zones are developed or in altered use (cultivated, grassland, barren) and in some subwatersheds this number is over 50%. As we learned last week, this results in significant changes in the quality and patterns of delivery of water into the system. Without natural land to absorb excess rain and filter contaminants, greater concentrations of contaminants such as oil and grease from streets and parking lots, bacteria, lawn care products, and heavy metals enter the estuary in stormwater. Due to the land use patterns of the Bay system, polluted runoff is a greater concern in the northern portion of the system. In addition, the natural substrates could absorb rainfall and slow its flow, reducing the "buffering" of the system against storm surges and thus in increased incidences of flooding in low-lying areas. The loss of filtration within the system means that pesticides and herbicides in residential and agricultural areas within the watershed reaching the estuary faster and in higher concentrations. Storm surges also increase the amount of halogenated hydrocarbons which enter the Bay in both surface (though these also enter the Bay more slowly within the ground waters). Petroleum hydrocarbons and tracemetals also enter the Bay from marinas.
Groundwater withdrawals: Large volumes of groundwater withdrawals impact estuarine flows both by reducing tributary base-flows and by directly reducing the direct inputs of groundwater into the estuary. Between 1989 and 1992 for example, groundwater withdrawals from the Kirkwood-Cohansey aquifer were 5.87 x 107 l/day, which decreased the average base flow in several streams in the watershed to less than 12% of their pre-development levels. As ground water is an important source of freshwater to the Barnegat Bay, the continued and growing levels of groundwater usage can be expected to have a significant impact on the water budgets of the estuary. Other effects include lowered water tables and saltwater intrusion into aquifers, which could limit the supply of drinking water for the residents in the area.
Some estuaries with abundant industries have received high doses of trace-metals, especially in the past (before such outflows were highly regulated). For example, Baltimore harbor sediments are so contaminated with trace-metals that researchers cannot handle the mud without specialized hazardous-waste equipment (clothing, and in some cases breathing systems etc). Particularly damaging were smelting plants and photographic companies (silver nitrate used in developing). Other trace-metal sources in estuaries include natural inputs (erosion of surrounding rocks if the drainage basin is rich in metal-containing bed-rocks), anti-fouling paints and preservatives used to preserve materials used in bulk-heading. In the last few decades, problems associated with trace-metals (especially tin) in anti-fouling paints have been well documents (particularly impo-sex (presence of male genitalia on females, leading to sterility in advanced cases) in gastropods and lesions on the livers of vertebrates). Consequently many previously popular anti-foulants have been banned (except in the navy!). However, even currently legal paints can still impact aquatic systems, especially when boats are in high density (as in harbors, especially those with limited flushing with the larger system). Similarly, many of the compounds that are used as preservatives for wood used in marine construction (bulk-heading, docks etc) contain cupric compounds. The presence of large quantities of bulk-heading, especially in areas with poor flushing has been shown to result in copper accumulation in many shellfish and fin-fish species. While the health effects of such trace metal accumulations are still being debated, as is the implications for human health of ingestion of such organisms, it seems clear that, as human impacts on estuaries increase, the impacts of these types of pollution will also increase unless regulations are changed. Sewage can also be a source of trace metals. This problem is exacerbated because the process by which sewage sludge is treated to remove most of the organics has the effect of concentrating any trace metals in that material. These trace-metals can sometimes be present in fairly high concentration in sewage sludge. Fortunately for estuaries such sludge is usually dumped at sea, or recycled on land (you can buy it as fertilizer for example!).
Trace metals are somewhat of a problemin the Barnegat, with moderate to high concentrations of arsenic copper lead and zinc being documented from the bottom sediments of the Manasquan, arsenic, copper, lead and mercury in the Metedeconk, arsenic and lead from Double Creek Channel and Arsenic from West Creek. Lower levels of trace metals are present in sediments throughout the bay. Of those, cadmium, chromium, lead, mercury and zinc concentrations (often enriched near marinas) being sufficiently high to adversely affect estuarine organisms. Biomagnification of these toxins may pose health risks to humans and other predators within the system. High mercury levels have been found in the eggs and feathers of several colonial-nesting bird species in the Barnegat Bay, such as Forster's tern, black skimmer, great egret and snowy egret. The levels found in the eggs of some of these were in the range known to have serious impacts, such as increased embryo and chick mortality, reduced hatching and reduced chick weight. In a study of tern eggs in the Barnegat Joann Berger found that some of the metals of concern in estuarine environments (lead, cadmium, chromium) have declined in terns in Barnegat over past 30 years. However, while lower than at their peaks, mercury levels in tern eggs are currently higher than they were in the early 1980s and a spike in mercury levels in tern eggs in the Bay in1999 is still unexplained. Levels of other trace metals (notably selenium and manganese) showed no trends throughout the duration of Berger’s study (1970s to early 2000s).
Disease-causing microorganisms found in human and animal wastes also enter the Barnegat Bay through urban stormwater, sewage treatment plant discharges, boating waste, and individual septic systems. As we learned last week, these organisms can result in illness (Gastroenteritis, hepatitis) in people who eat contaminated shellfish or who come in physical contact with in beach waters. Following heavy rains, many of Barnegat Bay's beaches are closed for public health reasons. In addition, restrictions on shellfish harvests resulting from high levels of pathogens are common in the northern portion of Barnegat Bay and its tributaries. For example, in 1990, 44 percent of all shellfish beds in Barnegat Bay were harvested-limited, primarily due to pathogen contamination. However, in 2004, 80% of Barnegat Bay and Little Egg Harbor still had sufficiently high water quality to be classified as “Approved” for shellfish harvesting and things seem to be improving: Between 2000 and 2004, 336 acres were upgraded and only 84 acres were downgraded. By contrast, only about 20 backbay beach closings each year were reported from 1988 to 1995 due to high fecal coliform counts. In the 70s elevated fecal coliform counts were mostly associated with sewage treatment plant outfalls. These sources were removed by construction of new treatment facilities toward the end of the decade. Since then elevated coliform counts have tended to be associated with increased development and non-point source runoff. From 1995 – 2004 the number of closures ranged from a low of 18 in 2001 to high of 135 in 2004, with the variability in those numbers largely being due to the number, duration and intensity of rainfall events immediately before and during the recreational bathing season. The largest number of annual closures has occurred during 3 of past 4 years, suggesting a rapid downward trend in water quality with regard to this parameter.
Accumulation of trash on the beaches can be unsightly, and may also impact wildlife in the system. The amount of trash on Barnegat's shores continues to be large. For example, in a 2-day beach clean up in October 1994, volunteers cleared over 73,700 pounds of trash from 171 miles of New Jersey's beaches. Of this material, more than 66% was plastics more than 10% was paper and another 8% was metal, with the remaining 15% being made up of a variety of other materials.
Many companies (especially power companies) choose to locate on estuaries specifically because of the abundant water supply that can be used as an inexpensive coolant. The water that they emit is considerably warmer than that of the input. Such thermal loading may significantly change the temperature of the water downstream of the heat source. This can have a wide variety of effects. For example Some stretches of the Hudson River in New York no longer freeze in winter because of the flow of hot water into the river from adjacent power plants. Such changes potentially effect the kinds of plants and animals present in a number of ways. For example, warm water may create a thermal barrier to movement through estuaries for anadramous or catadramous species, potentially interrupting migratory patterns of animals in the affected areas (e.g. Manatees in Florida). Similarly, the warm water may cause fish eggs to hatch before their natural food supply is available or, alternately, it may prevent fish eggs from hatching at all.
In the Barnegat Bay the major source of heat pollution is the Oyster Creek plant. About 1.4 billion gallons of water or 2.3% total volume of Barnegat Bay passes through antiquated cooling system each day. Water temperature in the discharge canal can reach 110ºF. This warm water causes calcification (calcium precipitation) of the receiving waters. The heat causes physiological and behavioral changes in organisms in the area that may increase mortality. Some of these behavioral changes include:
– Increased metabolic rate of organisms resulting in decreased growth and survival, especially in summer when ambient water temperatures are at peak
– Avoidance of Oyster Creek by certain species during summer and early fall.
– Attraction to Oyster Creek during winter when species should have migrated out of the area due to cold temperatures can lead to large-scale mortality (due to thermal shock) when plant has planned or emergency shut down.
• January 1972 - December 1982 reported 2,404,496 fish killed due to thermal shock including Atlantic menhaden, bay anchovy, bluefish, striped bass and weakfish
• Emergency shutdown on January 21, 2000 caused a 17ºF drop in water temperature in discharge canal in 15 minutes resulting in death of ~3500 fish including 2980 striped bass.
• Similar event November 11, 2001 caused a 7ºF drop in water temperature in discharge canal in 15 minutes resulting in death of ~1400 fish
• Scheduled shutdown on September 23, 2002 increased water temperature in discharge canal to 101ºF in less than an hour resulting in death of ~6,000 fish
Radionuclides also enter Bay from Oyster Creek Nuclear Generating Station. Of 76 US nuclear sites, Oyster Creek reported the 2nd highest airborne releases of radionuclides with a half life of eight days or more. 76.8 curies of such radiation have been released from the plant since 1970 (for comparison, the Three Mile Island Unit 2 accident in 1979 released 14.2 curies). Reactor-released radionuclides (60Co, 137Cs, 54Mn) detected in water, bottom sediments, benthic marine algae, seagrass, hard clams, blue crabs, bunker, winter flounder, summer flounder, bluefish and several other fish. Organisms collected near Oyster Creek had highest levels but detectable levels were found throughout bay. In addition, sediments near the discharge canal have 60Co levels up to 63x higher than those elsewhere in Barnegat Bay-Little Egg Harbor estuary
The operation of the Oyster Creek is also associated with a number of other problems within the Bay. The discharge water from the plant is high in chlorine (since bleach is used as a biocide in plant's pipes). This chlorine directly kills the phyto- and zooplankton that were entrained in cooling system and can impact organisms residing in discharge canal and surrounding waters. However, a bigger problem is number of organisms crushed against intake screens after being entrained in the plant’s intake waters. Plant records indicate 32 impingement and 14 mortalities of endangered sea turtles since 1992. 21 of these were Kemp’s Ridley Sea Turtles (9 mortalities), 7 were Loggerhead Sea Turtles (2 mortalities) and 4 were Green Sea Turtles (1 mortality). Between November 1984 - December 1985 one study reported that 22 million fish (mostly larvae) and invertebrates were impinged on the plant’s filters (7 million in December 1985 alone). Another study carried out between September 1975 and August 1977 9.19 x 1013 microzooplankton (<500 μm including copepods and clam, snail, worm and barnacle larvae) and 4.24x1011 macrozooplankton (>500 μm including jellyfish, sand shrimp, grass shrimp, larvae of sandlance and American eels, eggs and larvae of winter flounder, and several crab species) were entrained and sucked right into the plant (passed through the filters). Once entrained, organisms are subjected to numerous and potentially fatal insults including:
– 1) Thermal shock from the sudden increase in water temperature (12-13ºC).
– 2) Shear and pressure forces from high water velocity and trapped air.
– 3) Mechanical stress from contact with machinery, pumps, etc.
– 4) Lethal levels of chlorine injected daily into the condenser section to reduce biofouling.
The damage caused to the ecosystem by organismal entrainment by this plant is exacerbated by the fact that the facility increases its water usage in summer, a time that coincides with peak concentrations of eggs, larvae and plankton in the water column. It is believed that the plant negatively impacts organismal diversity and abundance in the Bay. However, specific studies on these impacts have yet to be carried out.
Habitat Loss and Degradation
While nutrients, pollutants, river flow and overfishing are all important, the problem of destruction of estuarine habitat by reclamation, marsh drainage and other engineering works may, in the long run, be the most important, and the most difficult hardest problem in estuarine management. The pressure to develop areas near estuaries is ever increasing, and there is a great deal at stake in terms of money, potential employers and tax-base at both the state and municipal level. Against this pressure, estuarine managers need to provide realistic assessments of the impact of the lost area, not only in terms of food resource and habitat for wildlife, but also as a "free nutrient filtration" system and sediment trap. Such information is often not easy to come by, especially on the time scales required. Education of the public and of policy makers is imperative if estuarine managers are ever going to be able to be effective in balancing all the conflicting users of estuarine ecosystems
The loss or modification of habitat takes a number of forms in the Barnegat Bay:
· Bulkheading About 45% of the Barnegat Shore is affected by bulkheading. In addition to the problems of chemicals leaching from the bulkhead materials that we discussed this week, bulkheading also contributes to storm surges by maintaining water in narrow channels. It also reduces the amount of channel bank habitat within the system, and thus limits any processing/filtration of nutrients and toxins that would normally occur in these systems, as well as negatively impacting the abundance of organisms that depend on such habitats.
· Fragmentation. Biogeographical principles suggest that diversity increases with the size of the unbroken habitat patch that is present. Thus division of habitat into fragments by water, roads, houses etc destroys not only those organisms within the immediately impacted area, but also those which require the larger expanses of habitat for their survival. Due to the patterns of development, forests in the east of watershed are more highly fragmented by roads and development than are those in the west of the watershed and habitats toward the North of the Bay are more strongly impacted than are those in the South.
· Loss of Wetlands and SeaGrass Beds: New Jersey has lost over 584,000 acres, or 39 percent, of its original wetlands largely due to dredging and filling, with many of these wetlands losses occurring along New Jersey's coasts. In the Barnegat Bay watershed, significant acreage of both coastal and freshwater wetlands has been modified or destroyed. For example, between 1953 and 1973, over 37,000 acres of tidal wetlands were destroyed in Ocean County - a loss of over 30 percent. However, despite this loss approximately 8,850 ha of original tidal marsh remain. The seagrass beds of Barnegat Bay represent 75% of New Jersey's total SAV with the western portion of the Bay supporting narrow, beds of Zostera marina, while the eastern portion is the site of larger, more expansive meadows and the Little Egg Harbor region being the southern limit of eelgrass in New Jersey. In the shallower and less saline reaches, the Z. marina beds give way to widgeon grass Ruppia maritima. After the wasting disease epidemic of the 1930s, the eelgrass beds appear to have recovered substantially by the 1950s. However, comparison of the extent of seagrass beds between the '70s and '80s with that in the '90s shows a decrease of over 33% (though differences in methodology between surveys make it difficult to know if this reflects methodology or true die back). However, it seems highly likely that eelgrass in the estuary has been adversely affected by increased nutrient inputs and human activities, such as dredging and boating associated with the dramatic population increases in the region over this period. In addition, during the summer of 1995, there was a massive die-off of eelgrass in the Central Bay region, reportedly due to an occurrence of the wasting disease (Labyrinthula zosterae). Similarly the biomass of seagrass beds in the Barnegat Bay-Little Egg Harbor Estuary in 2006 decreased by 50-88% compared to 2004-2005. The losses and degradation of these habitats can dramatically affect the environmental quality and biotic community of the system. In particular, the concern is that these effects will result in a loss of overall biodiversity, and perhaps loss of the numerous endangered plant and animal species found in the area.
· Dredging: The fine sediments of the Barnegat Bay and the shifting sands of the Barrier Islands to its East mean that, to maintain access to the Bay for the numerous boats using the area, dredging is more or less a necessity in the system. The volume of sediments dredged from the inlets of the estuary have ranged from about 10,000m3 at Manasquan Inlet in 1965 to 1,150,000 m3 at Barnegat Inlet during the major restructuring effort of 1987-1991 which was carried out to try to reduce sedimentation in channel. Dredging continues annually within the Barnegat Inlet in order to maintain a 16 foot channel for boat use. Sediment removal in inlet has exceeded 200,000m3/yr from 1993 to 1997, with largest volume of sediment dredged in 1997 (277,692m3). The sediment removed in these efforts is either used in beach replenishment or dumped offshore. While, in reality, this is an unavoidable evil as a result of the need to maintain a navigable channel for shipping, the negative effects of dredging are numerous. Obviously dredging has a direct impact on the organism in the dredged area, as it removes them and/or the sediment in which they make their homes. However, dredging also has a number of indirect effects in the area around the dredge site, including the suspension and subsequent lateral transport of fine sediments, which may shade out near-by eel grass beds, or suffocate sedentary organisms, such as oysters, in the region. In addition, if the sediments contain any toxic contaminants, dredging may reintroduce these constituents into the water column. In recent years the amount and timing of dredging efforts in the Barnegat has been strongly regulated to try to minimize its impact, as has the disposal of the dredge spoil. However, it seems likely that it will never be possible to completely eliminate this activity in this region.
· Recreational Boat Use Due to the population densities near estuaries, and the long lengths of water-side property in estuaries, water sports are often an important recreational use of estuaries. For swimmers the main concern is for human health (is the water relatively free of pathogens), as well as potentially conflicting species (jellyfish, crocodiles, sharks). However for other sports (boats, especially motor boats or jet skis), the concerns are directed in both directions: From the human side, highly eutrophied waters, especially those suffering from nuisance blooms are less desirable for recreational uses than are pristine clear waters. Unlike swimming though, these activities can have strong impacts on the system. Motor engines are poorly regulated and often have significantly higher emissions levels than do more highly regulated terrestrial vehicles. Boat engines are also renowned for leaking oil into the water (ever looked at the water in a harbor and not see an oily rainbow?). Poorly regulated sewage disposal from marine heads, and poor garbage disposal practices of many boaters add to estuarine pollution. Other problems associated with boat use center around the erosion of marshes and mudflats along the shore lines as a result of the wakes created by motor boats and the damage done to grass beds, oyster beds and, to a lesser extent, marshes by propellers (prop scars). Regulation of access and /or boat speeds to reduce these effects is sometimes attempted using posted signs. However policing of these regulations is often weak and ineffectual and the damage to sea grass beds, oyster beds etc continues to be a problem in the shallow waters of most heavily used estuaries.
In the early sixties "extreme critical" boating use intensity, as defined as a level that would have a significant toxic effect on fish life, was determined to that level which resulted in use of 18 gallons of fuel per acre-foot of lake volume per year. Eleven years later in a study of 5,100 acre Lake Geneva, Wisconsin "Saturation Boating Use" was estimated to be 15 gallon per acre-foot per year fuel use (assuming a 5 month boating season). Using figures for recreational boating fuel use in New Jersey commissioned by the U.S. Fish and Wildlife Service, it was estimated that 10,344,000 gallons of fuel was used in recreational boating on Barnegat Bay in 1990. This represents a usage level of 50 gallons per acre-foot per year, yet this study hasn't generated any discernible concern. Apparently, what were once considered to be "worst case" levels of boating activity are now treated as "normal". Such intensive boating activity may negatively impact the estuary in a number of ways:
o Direct physical stresses on aquatic organisms caused by vessel operation, such as impacts by the edges of propellers or hull parts as well as propeller-generated turbulence and shear forces. Surprisingly scientists don't really know exactly how large these forces are for a specific type of engine or boat-type, nor are they totally sure how much force is needed to cause a specific level of injury or death to particular organisms. However, in laboratory tests on paddlefish and carp, significant differences in mortality were noted in larvae exposed to low versus high levels of turbulence similar to those resulting from boat engines. This it seems likely that the disturbances to the water column caused by boats and their engines may be responsible for injuring or killing aquatic organisms especially the more vulnerable eggs and larval stages.
o Negative impacts on the physical environment caused by vessel operation such as increased turbidity and disruption of stratification. Clearly, isolating what portion of turbidity present in an estuary is attributable to boating activity and its impacts versus that occurring normally or resulting from other anthropogenic activities is difficult. However, it seems likely that, in a shallow water body with silty sediments, like the Barnegat, boating activities could play a large part in resuspending sediments and, particularly with the finest fractions, in keeping them in suspension. Along with the sediment-associated increases in turbidity associated with turbines and boat wakes, disturbance of sediments may also contribute to increased turbidity indirectly by making nutrients more readily available to the phytoplankton. While it is possible that intense boating activity might disrupt estuarine stratification, this has never actually been documented. However, by estimating the volume of water that would be swept by the propeller of a boat moving at 30 miles an hour, it can be determined the 19,000 boats documented to be in commercial storage (marina slip and rack) on Barnegat, would sweep a volume of water equivalent to the entire volume of the Bay in only 3 hours of combined operation. Clearly, this is only an estimate. However, it seems likely that the organisms of the bay, and particularly the more fragile eggs and larvae would be strongly affected by the high levels of boat-use seen in the region in summer, which is also a time when those vulnerable forms are at their most numerous.
o Biological effects of pollutants, particularly hydrocarbons, from boat engine emissions. The hydrocarbons and heavy metals released from engine combustion are known to be adsorption onto suspended particles and in the flocculent layers of bottom sediments. In addition, such microlayer-contaminants have been shown to result in increased chromosomal aberrations in developing fish embryos and in reduced hatching rates of sole fish eggs, at least when they are present in high concentrations. Again data on engine emissions is not available for the Barnegat but, based on sales of boat engine fuel and on the average discharge of emissions by boat engines, it has been estimated that between 200 and 500 tons of engine emissions material ("...found to contain parrafinic, olefinic and aromatic hydrocarbons, as well as small amounts of phenols and carbonyl compounds." Breidenback, 1974) are put into the system from boat engines annually. Many species of fish, such as the bay anchovy (Anchoa mitchilli) bluefish (Pomatomus saltatrix) striped bass (Morone saxatalis), weakfish (Cynoscion regalis), summer flounder (Paralichthys dentatus), American oysters (Crassostrea virginica) and hard clams (Mercenaria mercenaria) spawn in the estuarine reaches of the Barnegat. In all these species larval development and/or maturation occurs during the peak of the recreational boating season. Moreover, they are generally found in the upper water column, which means that they are more likely to come in contact with the freshly input toxins. Given that it is these immature (eggs, larvae or juveniles) forms that are most susceptible to these toxicants, and the fact that these organisms are often simultaneously being stressed by low oxygen levels and/or high water temperatures, perhaps it’s not so surprising that all these species are experiencing serious stock declines!
Organisms in estuaries are being hit from all sides. As we’ve seen, many are experiencing severe habitat reductions or reductions in their habitat quality. At the same time, many commercially important species are under increasing pressure from both commercial and recreational fisheries. The combination of these factors have meant that many estuarine species (oysters, scallops, salmon, striped bass etc) have undergone precipitous declines in their abundances in recent decades. Regulation of fisheries by such measures as licensing, size limits and catch limits is often harder to achieve than you'd think, as both commercial and recreational fishermen are fairly popular with the electorate and regulation of their activities is often heavily opposed by voters (recreational) and lobby groups (commercial).
Status of Major Fisheries in Barnegat Bay: A number of species are exploited within the Bay. Here though I am only going to consider the species which contribute most to the fisheries within the bay. Eel landings started in the Bay in the 1950s and gradually increased to maximum of 31,311 kg (69,579 lb) in 1971. Overfishing had the usual effects and the fishery declined after that. From 1989 to 1994 annual commercial landings of the American eel in Barnegat Bay declined from 17,303 kg to 4,095 kg (9,100 lb to 38,450 lb). No more recent data are available, suggesting that the fishery has largely ceased within the Bay. Similarly, a rapid decline in winter flounder landings occurred between 1989 and 1991, from 2,671 kg to 1,175 kg (5,935 lb to 2,610 lb). Changes in management (harvestable size limits, bag limits) for this species resulted in relatively strong recovery to levels consistently near 1,800 kg (4,000 lb) since then. In 1988 the clam fishery within the Barnegat Bay contributed 80% value of commercial fisheries in Ocean County ($2.2 million). However, overfishing combined with negative effects of eutrophication (brown tides) which contributed to poor recruitment success in this species, resulted in a nearly three-fold drop in hard clam landings between 1989 and 1990, from 370,090 kg to 133,533 kg (822,423 lb to 296,740 lb). This decrease meant that the clam harvest from the Bay dropped from 70.1% to 23.9% of total hard clam landings in New Jersey. Between 1990 and 2000 hard clam landings slowly declined to 29,691 kg (65,981 lb) representing only 3.8% of total NJ landings. There has been considerable variation in the annual landings of blue crabs in Barnegat Bay from 1989 to 1997. Blue crab harvest showed peaks in 1991 (526,478 kg; 1,169,950 lb) and 1993 (627,404 kg; 1,394,230 lb). After 1993, landings in Barnegat Bay dropped steadily to a low of 207,423 kg (460,939 lb) in 1996 and then increased to 352,066 kg (782,369 lb) in 1997. From 1989 to 1997, blue crab landings in Barnegat Bay varied from 8.4% to 23.5% of total NJ blue crab landings.
The cost of losses to the fisheries within the Bay as a result of environmental degradation were recently evaluated by Bricker et al. (2007). In this study the authors collected data on the average actual catch of summer flounder per month for 1997-2002. They then used a statistical model (driven mostly by a hypothetical relationship between measured chlorophyll in the system and flounder productivity) to predict summer flounder catches under unpolluted (“improved”) water quality conditions. This allowed them to measure the losses in potential fish harvest that resulted from eutrophication. Using net value for mid-Atlantic fisheries they estimated that the negative effects of eutrophication on the summer flounder populations cost Barnegat Bay fishermen an average of $25.4 million per year for this species alone
This study suggests the huge value of managing fisheries in such a way as to protect the long term health of the fishery. However, in species where management strategies have been implemented the results have been mixed. Striped Bass populations which were nearly decimated by overfishing have shown strongly positive response after a moratorium was placed on catching this species (though management of the recovering population is still not without its problems). However, regulations on harvest of scallops and oysters, whose populations are critically low in many estuaries have often failed to result in the desired population recoveries.
Current Management Practices in Estuaries
The job of an estuarine manager is to balance the multiple uses of estuaries in such a way as to maximize the degree to which human uses of estuaries are balanced with the requirements for a healthy natural ecosystem. Estuarine Management is generally divided into three main areas: policy, planning and practice.
Policy: (The political framework through which estuaries are managed.)
As estuarine management is currently practiced, the first step in creating policy is to identify the standard of environmental quality which the policy is intended obtain/maintain. In some cases these are determined from national or international regulations. In others, policy is set by a state by state or system by system basis.
In international policies to regulate the discharge of toxic substances to estuarine waters, two levels of contaminants are recognized:
The composition of these lists was determined at the "Paris Convention" and has been adopted by many countries, and closely matches lists drawn up at the "London" and Oslo" conventions which addressed the regulation of dumping of materials into the ocean and the regulation of marine pollution.
To determine permitted levels of grey-list toxicants in discharges, toxicity testing (LD50 type tests) are often employed. Despite valid criticisms (these tests do not account for long-term effects of sub-lethal concentrations of a pollutant) the ease and reliability of acute toxicity testing mean that these tests are still heavily utilized in determining guidelines for effluent discharge. In the US the EPA and Coastal Zone Management Act (CZMA) have been the major federal instruments for protecting coastal ecosystems. However individual States have the freedom to produce legislation for their own shoreline, which has made it difficult to maintain Federal consistency. Consequently standards for estuarine management vary from State to State.
In most cases, the estuarine manager will identify the desired uses for a particular system and to develop a series of Environmental Quality Objectives (EQOs) that are compatible with those uses. An example of a typical set of EQOs for a typical estuary might be:
1. To protect all existing defined uses of the estuarine system (e.g. bathing, boating, water use for agriculture and effluent disposal).
2. To protect the ability to support the benthic biota necessary to sustain fisheries.
3. To maintain accessibility of the estuary to passage by migratory fishes at all stages of the tide.
4. To ensure levels of chemical and microbial contamination low enough to prevent ill effects from ingestion/contact by man or other organisms.
Clearly all of these objectives, except the disposal of effluent, require that the estuary be as free from pollution as possible. Consequently the disposal of effluent must be controlled, either by reduction of volume, by improved quality of treatment, or by good dispersion of the outfall. Near the mouth of the estuary mixing and flow may improve effluent's dispersal, whereas in the inner estuary water inputs will tend to be retained, rather than removed by estuarine flow. Consequently the amount and standard of effluent released may need to be regulated differently, depending on the part of the estuary into which the effluent is being released.
The second objective requires that no discharge into the estuary should obliterate the fauna in the vicinity of the outflow (e.g. pulp and paper effluent), and also requires that dredging and other engineering schemes that destroy the benthic habitat should be avoided.
The third objective at first glance would appear to regulate physical structures such as damming... which it does. But it also covers such barriers as hypoxia or anoxia. If oxygen content of the water is low enough, that too will create a barrier to migrating fish. As these problems are most likely to occur in summer, or at times of low tidal exchange, regulations should be stringent enough to cover this most problematic period, rather than an average condition, or that in a less problematic (more lenient) period.
The fourth objective is designed to eliminate problems such as the contamination of shell-fish by coliform bacteria, or toxins that may be injurious to someone eating them, or the reduction of access to waters for recreation (swimming, diving etc.) due to health concerns (again coliforms).
Adoption of such EQOs has been criticized as being unjust because they "unfairly" penalize towns or industries situated inland versus those nearer the coast in terms of regulations. Consequently, in some cases a number of Uniform Emission Standards have been adopted in which equal controls or standards are applied to all effluents, regardless of position of input in the estuary.
Planning: The process of resource allocation
Having specified the permitted standards for any effluent entering the estuary the estuarine manager must determine the rate at which inputs are entering the estuary. This is done by multiplying the concentration of pollutant by rate of flow to obtain the "load". The assessment of loading is often made difficult, however, by the fact that many sources of pollution have wide variations in both their concentration and flow rates.
Once this is done, the manager will then select for each estuary, permissible levels of pollutant discharge that will allow the estuary to maintain/achieve the desired level of environmental quality. However, in certain cases ("red list" items, whose control is recognized to be a priority), permissible allowable inputs of substances may be regulated at specific levels regardless of the nature of the water body into which they are discharged. (i.e. certain very toxic substances can only be present in minute concentrations, no matter how efficient the flushing of the estuary might be).
The usual process of implementing the management program is to first assess the state of the estuary, the quality of its waters and the condition of the biota at all times of the year. In addition the sources of all discharges impacting the estuary should be identified and analyzed. Having done this it is then possible to regulate the major sources of these by issuing permits stating permissible volume and composition for effluent from that source. These permits use as their basis what's known about the estuary and local or national standards for red, black and grey lists. In practice it's often not possible to have all the necessary background information before issuing permits in poorly studied estuaries. In these cases permits are often issued on a provisional basis and can then be modified in light of subsequent evidence of deleterious effects of the effluent.
The next step is to study the estuary so that its patterns of input and flushing are known. This data is used to determine the ability of the estuary under consideration to disperse, degrade or assimilate the pollutants which enter it (implicit assumption is in essence the solution to pollution is dilution!).
Practice: The techniques needed for implementing planning decisions
The management of estuaries has, in some cases, produced spectacular reversals in the conditions of estuaries, many of which had been impacted by decades, if not centuries of neglect and pollution. The clean-up of the Delaware Estuary is one of the best examples of this. Over 6 million people reside in the watershed of this estuary. In addition it houses America's second busiest port, second largest complex of oil refineries and petrochemical plants and one of the world's largest concentrations of heavy industries. Years of pollution and eutrophication had lead to this estuary being essentially dead- devoid of aquatic life. Now, thanks to a long-term management program, the estuary once again supports a variety of plants and animals and even a recreational fishery... although like most urban estuaries, its problems are still not over.
Increasingly scientists and managers are starting to realize that ecosystems are initially quite resilient to changes associated with environmental pressures. However, once a system is disturbed, restoration of that system may require more than simply reversing the pressure to the levels that were present when damage was first apparent within the ecosystem. In practice one often has to return the system to a much lower level of pressure before recovery is seen. Clearly, then, the trick is to not push the system past its tipping point in the first place! However, this is easier said than done, since we often don’t know how far we can push an ecosystem and have it stay stable until we pass the point of no return and that system flips to a new stable state from which it will be difficult to restore to the former (usually more desirable) functioning.
Management of Barnegat Bay
· It will allow individuals to give gifts or donations to a particular refuge, to be used only at that refuge. This should encourage donors who wish to support their local refuge rather than a nation-wide pool.
· It authorizes refuges to enter into cooperative agreements with local nonprofit organizations to work on projects or to provide services to the refuge.
· It will set up pilot programs involving full-time volunteer coordinators. So far this program is only being implemented at seven select refuges around the Nation, of which the Edwin B. Forsythe Refuge is one.
Specific Needs for Monitoring Water Quality of Barnegat Estuary
· Maintain improvements made to monitoring estuary in recent years
· Establish consistent, long-term monitoring of key biological measures of ecosystem health. Needed to assess:
· Impacts to estuary
· Degree of success of actions to mitigate those impacts
· Develop detailed modeling of hydrography of estuary
· Tidal flushing
· Relative roles of surface and ground water flows into estuary.
· Needed for better understanding of fate of pollutants entering estuary and to better model effects of proposed management actions prior to implementation.
Author Louise Wootton, Ph.D.
Last updated September, 2008.
Author Louise Wootton, Ph.D. Last updated September, 2008.