Georgian Court University

Introduction to Barnegat Bay and the Pinelands

The Barnegat Bay is an estuary (a place where rivers mix with ocean water so that the salinity is in between that of fresh and sea water).  It is located along the central shore of New Jersey and is bordered throughout by Ocean County. The system is about 42 miles long, stretching from the Point Pleasant Canal in the north to the Little Egg Harbor Inlet in the South.  The Bay is generally very shallow, averaging less than 6 feet deep and with a maximum depth of about 24 feet.

Separating the Bay from the Ocean is a series of barrier beaches and dunes.  In the North Bay is a barrier peninsula which is heavily settled from Mantoloking to Seaside Heights, but which has an undeveloped area, Island Beach State Park at its Southern End. 

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.

South of the inlet is the heavily populated Long Beach Island (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. The flow of fresh water from these rivers into the Bay, as well as important inputs below ground from groundwater, produces the estuarine salinities that are key to the survival of plants and animals living in and near the Bay.

All of the land from which water drains into the Bay is called the “Barnegat Bay watershed”.  The Barnegat Bay watershed is a 660 square mile area that contains all of the land and water in Ocean County, as well as parts of Monmouth County. It stretches to the east as far as the barrier islands and extends to the west as far as Plumsted Township; it’s bounded on the north by Point Pleasant Canal and on the south by Little Egg Harbor Inlet. The watershed varies from coastal dunes and marshes (much of which have been heavily developed) to interior pine barrens habitats protected from extensive development within the Pinelands.

More than 500,000 people live year around within the Barnegat Bay watershed and at least that many more visit the shore in the summer.  Moreover, since 1950, Ocean County has been New Jersey's fastest-growing county, with retirees being particularly attracted to the area.  As a result, thousands of new homes have been built in the area in recent years-including 72 senior citizen communities with more than 52,000 units. Development is particularly heavy in the northeast and on the barrier islands and is much sparser in the southeast as well as in the western Pinelands or Pine Barrens Areas.

The Pinelands or NJ Pine Barrens

At over 1 million acres the Pinelands represent 22% of the state's total land area and includes portions of seven counties (Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester, and Ocean

Given the location (between Philadelphia and New York), and the enormous and growing pressure for space in New Jersey, why are the Pine Barrens relatively free from development? The answer is that is that both federal and state legislation protect it from development, mostly to try to protect the water resources of the Kirkwood-Cohansey and Atlantic City 800-foot sands, both of which underlie the pinelands.  (These water resources are vital to NY, PA and numerous other cities and towns in the area).  In 1978, the United States Congress passed a law which protected about one million acres of this part of New Jersey as the “Pinelands National Reserve”. This, along with New Jersey’s Pinelands Protection Act (1979), strongly limits how much development can happen in each area of the pinelands. In some areas it is totally impossible to build new buildings, roads etc, while others, like Whiting are designated as “growth areas” where development is allowed, and is currently occurring rapidly

The Barnegat Bay system and the nearby Pinelands are home to an abundance of wildlife.

Barnegat Bay Plants

SAV:  Below the water, two kinds of plants are highly visible: macroalgae and seagrasses. These two together are referred to as “submerged aquatic vegetation” or SAV. As on land, only a few large plant species are common year-round due to the sensitivity of most of the species to changes in day length, light intensity and water temperature. In general the widest variety of species are found in late spring, though the biomass (weight of living plant material) is often higher in summer. 

The most common macroalga in the Bay today is the sea lettuce.  This species is used for food and shelter by some animals, but nutrient pollution can make it grow to excess, forming thick mats that suffocate the other plants and animals in the system. By contrast, the most common seagrass in the system, eelgrass, is negatively impacted by nutrient addition. While eelgrass is common on sandflats near the inlet, another seagrass called widgeon grass is found in the more upstream, lower salinity areas of the Bay.

SAV species provide a lot of food for the animals of the Bay. Their tall blades also form an import habitat for estuarine animals, providing them with places to sit and ways to hide from their predators as they feed. As a result, many commercially important species of crabs and fish use seagrass beds as places to spawn and as “nurseries” for their young. The seagrass blades also slow the currents within the bay, which helps prevent erosion and keep the water column clear enough for plants living on the bottom of the bay (termed “benthic”) to do photosynthesis.


Phytoplankton:  Much less visible, but possibly more important in the Bay are free-floating, microscopic plants called phytoplankton.  More than 180 species of phytoplankton have been reported from Barnegat Bay, with different species being present at different times of the year, or areas of different salinity, nutrient or light availability.  Phytoplankton abundance tends to be maximum in summer when their densities can reach 800,000 cells/ml and minimum from late fall to mid-winter when densities fall to 80,000 cells/ml. 

Some types of phytoplankton like a group of tiny golden algae with silicon shells called diatoms are good sources of food to the shrimp, fish and other animals of the Bay.  However, others, such as the super-tiny brown-tide algae cannot be eaten by most animals, and indeed may often be so distasteful to scallops and other animals in the Bay that, when they are present, those animals will refuse to feed, even if that means that they starve to death.

Phytoplankton tend to respond very quickly to nutrient additions, so they tend to grow more densely in nutrient rich water. When there "Blooms" happen, the algae can actually become so numerous that they shade the areas below them, which can negatively impact the seagrasses rooted in the mud below.

Barnegat Bay Animals

Crustaceans:  The most important crustaceans of the bay are probably the tiny zooplankton.  These microscopic shrimp-like animals eat the phytoplankton and, in turn, are an important food for the Bay’s juvenile fish, clams and other animals.  Sand shrimp and grass shrimp are a little larger and often graze on smaller animals, or fragments of SAV, and these too are important food source for larger fish. Larger crustaceans like blue crabs and horseshoe crabs are also common in the Bay. 

Blue crabs are voracious predators, using their powerful claws to crack open clams, or to capture small fish or other crabs. Male and female blue crabs can be told apart by the appearance of their abdomen.  The male's abdomen is long and slender, whereas the female’s is much wider and more rounded. 

Blue crabs (and all other crustaceans for that matter) grow by molting or shedding their hard outer shell.  When they emerge they have a soft shell (this is what you’re eating if you’ve eaten a soft shell crab).  They then blow up their tissues with water and the new shell hardens around their swollen bodies.  Once the shell is hard (about 2-3 days later), they pump the water out of their tissues and there is then lots of room to grow before they must molt again.  When the female crab is mature, the male will detect that she’s about to mate and will attach to her (forming what’s commonly called a doubler).  That way he will be sure to be present and able to mate with her while she’s soft, right after her molt.  The female will then use the sperm from that mating to fertilize all the eggs that she makes in the future.  Like the clam, her fertilized eggs will be released into the water column, where they form a larvae that looks more like a tiny shrimp than a crab. These larvae will eventually metamorphose into tiny crabs that will live in the SAV beds as they mature.

Jellyfish:  In recent years the sea nettle jellyfish has been increasing in abundance in the Bay. Adult sea nettles are free floating animals with a bell that’s about  4” across, and tentacles that extend more than 2 feet below or behind them, on which numerous stinging cells are found.  Their favorite food is another gelatinous animal called a comb jelly, which doesn’t sting, though they do glow in the dark, which is kind of cool. You see sea nettles quite often in the summer, but not in the winter.  The reason for this is that these jellyfish spend their winters in attached to a rock or other hard surface at the bottom of the bay in a life history form called a polyp (looks like a tiny anemone).  In the spring, this polyp buds off tiny "medusae", which grow rapidly into the adult jellyfish.

Molluscs: the Barnegat once was home to abundant shellfish including oysters, scallops and mussels.  While these are still present, they are much less abundant today, and the most valuable clam harvested today is the now quahog (a type of hard clam).  These clams are called bivalves because they have hinged shells made up of two halves or valves. Like most bivalves, quahogs obtain their food by "filter feeding."  They live buried in the mud. Water is taken in through a tubelike siphon and passed over the gills which are specially adapted to filter out food (microscopic algae and other small organic particles).  The filtered water is then expelled via another siphon.  A large clam can filter about a gallon of water in one hour.  These animals spawn (put eggs and sperm into the water) during the summer, and the fertilized eggs hatch into larvae that look totally unclam like.  These larvae float around in the plankton for a while before sinking and metamorphosing into juvenile clams.  Other molluscs like moonsnails and whelks crawl along the bottom of the Bay, feeding on microscopic algae and other particles on the mud or sand.

Fish: Many species of fish, including anchovy, winter flounder and striped bass can be found living in the Bay.  Of the more than 100 species of fish known from the Barnegat Bay, about 1/3 are year round residents.  Most of the rest visit the bay during the summer months, when many of them come to these waters to spawn, so their young can make use of the protection and food resources of the Bay’s SAV beds.

Reptiles: Diamondback terapins are true estuarine animals, being found only at salinities intermediate between fresh and salt water.  In the past these animals were so common that they (along with lobster) were served so often as food to slaves and servants that a law had to be passed limiting the frequency with which masters could make their slaves eat these foods. These terapins are still found within the Barnegat Bay today, but they are now so rare that they are a candidate for endangered species status. The diet of the diamondback includes small fish, bivalves and crabs which they catch and crush using their beak-like mouths. Female Diamondback Terrapins are larger than males, growing to 10 inches in length verus a mature male's 6 inches. The female deposits eggs in nests that she digs into undisturbed areas of beach and marsh within the estuary.  The eggs hatch 3 to 6 months later and the newly hatched terrapin then crawl to the water for the first time. 

Leatherbacks and other sea turtles, which migrate up the Atlantic coast as far as Nova Scotia during the summer and return to their nesting grounds along the southeastern coast of the United States in the fall, may also be seen in the Barnegat region, especially in Fall.

Birds: Thousands of waterfowl and shorebirds use the estuarine area for nesting including the great egret, piping plover, herring gull, and laughing gull. Additionally, tri-colored herons, endangered least terns, black skimmers, and snowy egrets nest in the area, however, the populations of these bird species are in decline. The Bay is also an important stopover point for migratory shorebirds using the Atlantic flyway as well as a critical over wintering site for many species including American black duck and Atlantic Brant Geese. For migratory songbirds too, the coastal marshes and barrier islands of the Barnegat Bay provide an important rest stop and feeding opportunity. For other songbird species, including warblers, thrushes, tanagers, flycatchers, orioles, indigo bunting, blue grosbeak, and yellow-breasted take the region's tidal marshes, maritime forests, and pine-barrens are important breeding grounds. Like the songbirds, many birds of prey, such as golden eagles, bald eagles, and hawks pass through Barnegat Bay during their (fall) migration, while others, like Osprey, frequently nest and hunt in the region.

Marine Mammals: The Bay is home to several breeding populations of otters. Bottlenose dolphins are common summer visitors to the Bay.  Other winter visitors to the Bay region include harbor seals and gray seals which are frequently found foraging for fish near the region's beaches and inlets between December and March.

Pinelands Plants

The name “pine barrens” refers to the area’s sandy, acidic, nutrient-poor soil, which was “barren” in the sense of being unable to support most of the crops grown by early European settlers.  However, they are far from barren in terms of wildlife.  Indeed, the pinelands are home to about 850 species of plant, over 90 of which are either threatened or endangered or are species of concern (which means they could soon be threatened or endangered).

Three major habitat types are found in the Pine Barrens:

1. The upland pine-oak forests which are dominated by the pitch pine, a tree that grows rather asymmetrically to a height of 40-70 feet and a variety of Oak species.  The pitch pine has a thick bark, which is very resistant to fire. In addition, pitch pine cones only open in extreme heat, so the seeds are released only after forest fires. As a result, these plants will only keep growing in areas where fires occur commonly as used to be the case in New Jersey’s pinelands. In four areas of the Pine Barrens the Pitch Pines only grow to a height of five or six feet.  These “Pygmy Pine” forests seem to result from a combination particularly poor soil conditions, high winds and presence of unusually frequent forest fires which stunt the growth of these trees.

2.  Lowland cedar-sphagnum bogs.  These low lying areas are more or less permanently wet and have very low (acid) pHs.  These habitats have very low oxygen levels, which means that organic materials decay very slowly within them and so the nutrient reneration that results from such decay is extemely inefficient.  As a result, these waters are extremely nutrient poor. A number of plant species have adapted to these soil conditions.  For example, some pinelands plants, like Pitcher Plants and Sundews, obtain much of the nutrients that they need by catching insects.

Pitcher Plants have jug shaped leaves that collect rainwater. Glands on their leaves secrete a sweet smelling chemical which attracts insects.  Inside the leaf, special downward growing hairs which act as traps, allowing the animals to enter, but not to leave.  Eventually the insects fall in the water in the bottom, die and are digested by enzymes secreted into the water and the resulting nutrients are absorbed. 

Sundew leaves are also covered with hairs.  These produce a sweet-smelling, sticky substance which acts as a glue, trapping small insects that land on them.  Again the trapped insects eventually die and their nutrients are absorbed by the plant.

There are approximately fifty-five plant species considered endangered in the New Jersey Pine Barrens. One of these is Swamp-Pink which as you might think, grows in wet areas such as swamps or bogs and makes a cluster of small pink flowers at the end of each summer atop a green stem that sticks up one to two feet from the leaves at its base.

(3) Aquatic streams and ponds.  The acidic nature of pinelands waters means that the plants of these systems tend to be made up of tiny, acid tolerant algae.  Mosses are also common in shallow waters, since they too are tolerant of low pH levels.

Pinelands Animals

Most vertebrate groups are not common in these habitats and the number of species occurring here is less than in the remainder of New Jersey.  Nonetheless, 39 species of mammal, 299 species of bird, 59 species of reptiles and amphibian and 91 species of fish have been recorded in New Jersey’s pinelands.  Some of these species are well adapted to the environmental conditions of the Pine Barrens and are numerous there, and rare elsewhere. 

For example, most aquatic animals need pH levels above 5, and the water in the Pine Barrens tends to be more acid than that (usually between 3.5 and 5).  As a result, the species of fish and amphibians found in the Pine Barrens, such as the brightly-colored Blackbanded Sunfish and the Pine Barrens Treefrog are unusually tolerant of acidic conditions. 

Pine Barrens Tree Frogs are only an inch and a half long when fully grown and are brightly colored.  Their backs are a bright, glossy green and chestnut browns, while their undersides are usually bright yellow. This endangered species feeds on small insects and other invertebrates and breeds in late spring.  They attach their eggs to plants on the bottom and those eggs hatch into dark green tadpoles in about three days. These tadpoles grow to about an inch and a half long before they transform into young frogs. Another interesting Pine Barrens animal is the Eastern Mudminnow. This fish is widely distributed in New Jersey, but is most common in the Pine Barrens where it remains hidden in dense vegetation or detritus. Although it has gills for breathing in water, this fish copes with the low oxygen levels of pinelands ponds by using its air bladder (usually used to adjust a fish's buoyancy in water) as kind of a "lung" to breathe air.

Few salamanders are common in the dry sandy Pine Barrens soils. However, the aquatic larvae of the Red Salamander are frequently found in Pine Barrens streams and it’s thought that the adults probably remain near these streams or live in nearby bog areas.  By contrast, reptiles are rather common in the Pine Barrens, with 30 of New Jersey’s 35 reptile species being found here. Particularly common are the terrestrial Box Turtles as well as the more aquatic Painted Turtles and Snapping Turtles.  Similarly, the Eastern Fence Lizard is so common in this area that it is sometimes called the Pine Lizard. Its gray, mottled coloration is strikingly similar to the bark of the pine trees it climbs for refuge when threatened.  

The most common snakes are the Pine Snake in upland areas and the Common Water Snake along stream and lakes. The poisonous and endangered Timber Rattlesnake occurs in the Pine Barrens, but is not common.

Unlike reptiles, the pinelands don’t support a wide variety of bird species.  Only about 1/3 of the bird species seen in NJ are seen in the pinelands, probably because of the lack of habitat diversity in these areas. An abundant bird in the pine barrens is the Rufous-sided Towhee which can often be seen noisily searching for food in fallen leaves or singing from a prominent perch. Other common birds of upland areas include Blue Jays, Carolina Chickadees and Pine Warblers.

Of about 50 terrestrial mammals found in New Jersey, 34 are found in the Pinelands, though none is found only in this habitat.  The most conspicuous pinelands mammal is the White-tailed Deer which has gone from being an endangered species in the 1950s to being so numerous in recent years that the species is starting to overgraze its habitat, and damage the trees and plants of the pinelands.  Beavers too have recovered their population after going extinct in the pinelands in 1820 and having to repopulate the idea from outside.  Although relatively common in today’s pinelands, beavers are rarely seen.  However, you can see the evidence of their presence in the form of gnawed trees along many pinelands rivers. River Otters and Long-tailed Weasels also live along the streams of the pinelands. The pinelands are also home to three kinds of squirrel: Red squirrels are present throughout the Pine Barrens; gray squirrels are more characteristic of peripheral areas and Southern Flying Squirrels are common but rarely seen


Human Use of the Barnegat Bay

Tourism/Recreation: Tourism generates more than $3.25 billion annually in Ocean County alone and generates tens of thousands of jobs in the area. Popular activities in both the Bay and the Pinelands include hiking, hunting, swimming, fishing, and boating. In 1988, over 53,000 boats used the Barnegat Bay and over 116 marinas and other boat launching sites are situated within the watershed. In addition, the waters within Island Beach State Park, Edward B. Forsythe National Wildlife Refuge, Manahawkin Wildlife Management Area and the many other parks within the Pinelands, are popular destinations for canoeists and kayakers. Both Little Egg Harbor and Barnegat Bay are heavily used by recreational fishermen and supports a number of small businesses which cater to anglers in the region.

Commercial Fisheries/Seafood: Barnegat Bay and Little Egg Harbor sustain important local and regional fisheries. The estuaries and their surrounding wetlands are important nursery areas for a variety of shellfish and finfish, many of which are commercially valuable. Prominent species of finfish harvested from the system include winter flounder, menhaden, and striped bass.

 Another important species harvested from Barnegat Bay is the blue crab, with the harvest from this area contributing about 10 to 15 percent of the State's total blue crab landings. However, the most valuable commercially-caught species is the inshore hard clam or quahog. Between 40 and 50 percent of all commercial inshore hard clam landings in New Jersey occur in Ocean County waters area and the clam fishery contributes up to 80% of the total value of commercial fisheries in Ocean County ($2.2 million in 1988). In 1988, the estimated value of the combined commercial landings of quahogs, blue crabs, white perch, and American eels in Ocean County was $2.7 million. However, since 1990 there has been a substantial decline in commercial landings of quahogs (more than 75% decline from 1991 to 1996), apparently as a result of overharvesting and lack of success of the remaining animals to successfully produce surviving young (its not clear why not… are the densities not enough for the egg to find sperm in the water column or is something eating the young?).

Cooling Water: The Oyster Creek Nuclear Generating Station power-plant in Lacey Township (near Forked River in Ocean County) was built in the mid-1960s on the western side of the Bay, across from the Barnegat inlet.  It is one of the oldest nuclear power plants in the US and so uses a very outdated method for cooling its reactors that requires a huge amount of water. The plant began operation in December 1969 and since then has drawn1.4 billion gallons of Barnegat Bay water per day into its “once-through” cooling system from the Oyster Creek and the southern branch of the Forked River. (Newer power plants used "closed cycle" cooling, which uses cooling towers to allow them to reuse the water used to cool the nuclear reactions.  Such technologies cut water use by plants like this by about 95%).

Residential: The primary land use in the Barnegat watershed is residential development, with less than one percent of the watershed being used for traditional agricultural production, farms, or berry production. In current years the population within the northern part of the watershed has been increasing rapidly. For example, since 1950, Ocean County's population has increased 775 percent. As a result, the proportion of the watershed that is developed has gone from 18 to 21 to 28% in 1972, 1984, 1995 respectively, with much of this development occurring in the Northern portion of Barnegat, in large part because of the legal protections provided to the Pinelands in the 70s and 80s.

Associated with this development has been the loss of 13,700 ha (20%) of upland forest and 1875 or 6% of wetland forest between 1972 and 1995. Closer to the Bay the situation gets even worse: It is estimated that 71% of the Bay's Shoreline buffer zone (<1/10 of a mile from the water) is developed or in altered use, leaving only 29% under natural cover. This has resulted in over 28% of the Bay's marshes (4190 Ha) being lost to development, with most of this wetland loss having occurred between 1940 and 1970. Wetland loss was strictly regulated by the Coastal Wetlands Law of 1970 and, since that time, only about 1.5% of the wetlands have been lost to development. Today about 90% of Barnegat's remaining saltmarshes are currently protected under some form of public conservation ownership (like being part of a Federal, State or Municipal Park or being owned by a private conservation agency like the Nature Conservancy. However, wetlands in these protected areas are still being altered. For example, there are currently 950 km of parallel mosquito control ditches affecting about 2/3 of the Bay's Marshes. The situation is similar in other coastal habitats, with 70% of remaining undeveloped shoreline, 50% of Barnegat Bay's Islands and 45% of the inland forest habitat of the watershed being under some form of public conservation ownership.

Cranberry and Blueberry Harvest:  Other than tourism the only real industry in the Pinelands is berry growing. Wild cranberries and blueberries have grown in this area for thousands of years, since both plants thrive in the acid soils of the pinelands. Both wild cranberries and wild blueberries in the New Jersey Pine Barrens had long been picked and used by Native Americans long before Europeans arrived.  However, today’s commercial species have been much changed from their wild ancestors, growing much larger and yielding more and larger fruit than their forbearers. Indeed, the first-ever cultivated blueberries were developed in the Pine Barrens in 1916 by Elizabeth White of Whitesbog.

Today our state produces as much as 58 million pounds of cranberries a year, worth over 30 million dollars, on 3700 acres located in the Pine Barrens regions of Burlington, Ocean, and Atlantic counties.  As a result, New Jersey is now the third largest cranberry-producing state in the nation; only Massachusetts and Wisconsin produce more.  It is also the second largest blueberry producing state (to Maine), producing more than 40 million pound of blueberries each year, again mostly on lands in the Pine Barrens.

Environmental Challenges to the Barnegat Bay

Polluted Runoff: The sandy soils of the areas surrounding the Barnegat Bay mean that what happens to water on land rapidly affects rivers and the Bay. Because population densities in Barnegat region are rising fast, the watershed is 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 the areas surrounding the region's river are developed or in altered use (cultivated, grassland, barren) and in some watersheds of some of the Bay’s Northern Rivers, this number is over 50%. Without natural land to absorb excess rain and filter contaminants, more 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 in the Bay, polluted runoff is a greater concern in the Northern portion of the system.

Trace metals from a variety of sources including the treatments used to prevent rotting in wood used to build docks and bulkheads, and boat engine emissions, are also a problem.  Arsenic, copper, cadmium, chromium, lead, mercury and zinc (often enriched near marinas) occur in the Bay's sediments in concentrations sufficiently high to adversely affect estuarine organisms, at least in some areas. Because these toxins increase in concentration at each step in the food chain (a phenomenon known as biomagnification), these pollutants may pose particular health risks to humans and other “top” 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.

Hydrocarbons released from engine combustion are known to be adsorbed onto suspended particles and to bottom sediments. In this state, these contaminants can cause increased chromosomal abnormalities in developing fish embryos and reduce hatching rates of fish eggs, at least when 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 are put into the Bay from boat engines annually. Many species of fish, crabs and clams spawn in the Barnegat. In all these species, larval development and/or maturation occurs during the peak of the recreational boating season. Moreover, the larvae 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 toxins, 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 declines!

Pathogen Contamination: 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. 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.

Floatable Debris: Floating debris is caused by garbage washing into the system from street drains, as well as people throwing materials into the water from boats etc. Sometimes garbage is also released from dumps and even sewage treatment facilities. Accumulation of this trash on the beaches can be unsightly, and may also impact wildlife in the system. It can also result in beach closures as happened in September of this year (2007).  The amount of trash on Barnegat's shores continues to be large. For example, in 1999 over 600 tons of debris were removed from New Jersey’s beaches and as much again was collected off shore by NJDEP. 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.   

Nutrient Pollution: Probably the biggest problem in the Bay is eutrophication: the addition of excess nutrients.  As we have learned, 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. Nutrient inputs to the watershed have been increasing steadily in recent decades, with more than 75% of these inputs being associated with non-point source pollution (particularly fertilizers and pesticides from domestic lawns and golf courses, but fumes from car exhausts are an increasingly important source of nutrient pollution, equaling or even exceeding the amount of pollution that enters the Bay in surface and ground water, and pet waste is also an important contributor to nutrient pollution too).  As might be expected,  nitrogen inputs are larger from the Northern Estuary than those in the South.

These nutrients stimulate phytoplankton growth which then shades SAV limits the depth to which the seagrasses can grow in the Bay. Once they die, decomposition of the algae in the warm Bay waters may cause hypoxia or anoxia, even in the relatively shallow waters of the system.  In addition, stimulated by these nutrients, blooms of the "brown tide" algae have become increasingly common in recent years, which in turn have contributed to the decline of the quahog populations in the Bay.   

Problems Associated with the Nuclear Power Plant: The Oyster Creek plant discharges about a million gallons of warm water per minute into its discharge channel. This warm water causes calcification (calcium precipitation) of the water into which it flows. The heat in this water also causes physiological and behavioral changes in organisms in the area that may increase mortality. However, a larger concern is the large number of organisms that are crushed against the intake screens after being entrained in the intake waters. It is estimated that, 13 million fish and shellfish per year, such as larval and juvenile blue crabs, striped bass, winter flounder, bluefish, grass and sand shrimp, blackfish, bay anchovies, menhaden, spot, and spearing as well as a few seatrurtles and other larger animals are crushed on these filters.  However, these losses have not yet been shown to have significant effects on the overall community (they might have effects, but no-one has proved it yet).

The discharge water is also problematic because of the release of chlorine bleach (used as a biocide within the plant's pipes) and radio-nuclides in the effluent.  Surveys suggest that, even at their peak (in the 70s), radionuclide levels in the discharge waters have been well within regulatory limits and have declined in subsequent years.  By contrast, the amount of bleach in the discharge is 20x the lethal levels of many estuarine organisms like striped bass and bunker (another kind of fish). 

Habitat Loss and Degradation The loss or modification of habitat is another problem for the health of Barnegat Bay. This can take a number of forms:

Bulkheading: Coastal bulkheads are wall-like structures that are built along shorelines with the intention of controlling erosion. About 45% of the Barnegat Shore is affected by bulkheading. In addition to the problems of chemicals leaching from the chemically treated wood often used to build these bulkheads that we discussed earlier, bulkheading alsoreduces the amount of channel bank habitat within the system.  Since stream bank ecosystems are important filters for nutrients and toxins, bulkheading increases the level of pollution reaching the Bay's waters, as well as negatively impacting the abundance of organisms that depend on stream bank habitats.

Fragmentation. Species 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 in the Barnegat Bay System: 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.

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 eel grass, while the eastern portion is the site of larger, more expansive eelgrass meadows. In the shallower and less saline reaches, eelgrass beds give way to widgeon grass beds. 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 a 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 a disease caused by a slime mold, called seagrass wasting diseaseBecause eelgrass beds are such important habitats for many of the Bay’s animals, and are so important to the spawning and juvenile survival rates of many of those species, the concern is that the declines in the eelgrass beds that we have seen in recent years 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 a channel that's deep enough to allow access to the Bay for the numerous boats using the area, dredging is more or less a necessity in the system. The negative effects of dredging are numerous. Obviously dredging has a direct impact on the organisms 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 by stirring up the sediments, which then may shade out near-by eel grass beds, or suffocate bottom-dwelling organisms such as oysters. In addition, if the sediments contain any toxic contaminants, dredging may reintroduce these 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.

Groundwater withdrawals: The increased population in the Bay's watershed is also putting a strain on the Bay's water resources.  The water needed for all those people and their activities is taken mostly from the streams and aquifers underlying the watershed.  Large volumes of groundwater withdrawals impact estuarine flows both by reducing base-flows of the rivers and streams flowing into the Bay as well as by reducing the inputs of groundwater into the estuary. Between 1989 and 1992 for example, groundwater withdrawals from the Kirkwood-Cohansey aquifer were more than 15.5 million gallons/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 Bay by allowing seawater to push further and further upstream.  Since most animals and plants are adapted to specific salinities, such increases in the saltiness of the estuary would be expected to result in major changes in the types and numbers of estuarine organisms within the Bay.

Impacts of recreational boat use: In the early 1960s it was determined that the "extreme critical" boating use intensity (as defined as a level that would have a significant toxic effect on fish life) occurred when there were enough boats present to use18 gallons of fuel per acre-foot of lake volume per year. Using figures for recreational boating fuel use in New Jersey commissioned by the U.S. Fish and Wildlife Service, the boating use intensity of the Bay in 1990 was 50 gallons per acre-foot per year. Clearly, such intensive boating activity may negatively impact the estuary in a number of ways:

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.

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 that just the 19,000 boats in commercial storage (marina slip and rack) on the Barnegat (remember there are probably more than 2x this number on the Bay which are moored privately), a volume of water equivalent to the entire volume of the Bay would pass through their propellers 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.

Boat use also stirs up sediments, increasing the turbidity (cloudiness) in the system and can also directly scour (cut through) eel grass. Although it's hard to separate how much mud is stirred up by natural processes, like wind-driven wave erosion, from created by boat use, it seems likely that boat traffic could play a large part in resuspending sediments and in keeping them stirred up and in suspension. Such increases in turbidity could directly negatively affect SAV via shading from the suspended particle, and indirectly as nutrients released by the stirred sediments stimulate phytoplankton growth.

Global Warming and the Bay.  Global warming is expected to raise sealevels by 1-2 feet in the next century as a result of melting of land ice (melting sea ice doesn't affect sealevels since its already in the ocean) and, more importantly, the expansion of seawater as it warms.  In the Barnegat the effects of this would be likely to be more frequent flooding and much more damage to coastal homes and erosion of coastal beaches during storms. As sealevel rise, coastal dunes and wetlands will be flooded and be turned into open water, reducing the area of these habitats by more than half over this period.  Obviously, the density of homes along the low lying shore areas means that many homeowners are likely to lose their homes and property to erosion and flooding as the sealevels rise too.  In addition, the changes in temperature and salinity (as sealevels rise the ocean waters will reach further up the estuary, compounding the effects of decreased freshwater flow within the estuary) will change the number and kinds of animals in the estuary.  Warm-loving species will likely become more common, while cold loving animals will become rare or leave the estuary completely.  For example, it's thought that global warming might be one of the reasons that we've been seeing more frequent seanettle blooms in the Bay in recent years.  Seanettles thrive when water temperatures rise above 77 ºF, so the warmer summer temperatures that we've seen over the past two decades have probably contributed to that animal's recent success in the Bay

Nutrient Pollution:  As in the Bay, nutrient pollution is also a problem in the Pinelands, especially for the area’s streams, lakes and wetlands.  Many of the area’s unique plants are adapted to low nutrient conditions, and can thrive mostly because other species can’t grow under those conditions. When nutrient levels rise, the species which were once unable to grow in the area are now able to thrive and they quickly outcompete the Pinelands-adapted species resulting in a group of species much more similar to that you’d be able to find anywhere else.

Other pollutants: Pesticides and herbicides are used statewide for agricultural purposes (like spraying cranberries), lawn care, maintenance of golf courses, termite and mosquito control, etc..  Three of the four NJ counties that used the most pesticides are Pinelands counties:  Atlantic, Cumberland, and Gloucester (See Table below).  Many of the chemicals used in cranberry farming, for example, have been shown to harm SAV within the area’s rivers and ponds by affecting their seed germination, growth and photosynthesis

Table showing total pesticide amounts (by active ingredient) applied by counties of the Pinelands in 2000.  Percentage indicates portion of the state’s total use (New Jersey Pesticide Control Program 2000). 


Amount lbs.

% Total Use










Cape May












Total of state use



There are also a number of toxic waste sites within the Pinelands.  According to US EPA data, 58 National Priorities List (superfund) sites occur within the counties of the Pinelands..

Numerous other sites not severe enough to be classed as NPL sites also exist and threaten the quality of the area as well. These sites contain contaminants such as trichlorethylene, chloroform, toluene, phenols and heavy metals.  In most cases, these contaminants have entered the underlying groundwater and from there have entered the surface waters.  A recent study showed that exposure to the kinds of chemicals in these sites decreases the rate and percent of seed germination of selected species of aquatic and terrestrial vascular plants, and resulting in affected wetlands having many fewer species than expected. 

Altered Land Use: Despite the fact that much of the pinelands is protected from development, not all areas of the Pinelands are within the reserve, and even within the reserve some areas are allowed to be used for homes, cranberry or blueberry farms and other purposes.  As a result, some rivers have virtually none of their watershed affected by altered use, others have more than half of the area they drain in use for homes or agriculture.  As well as adding nutrients and toxins, agricultural use appears to result in increased pH (less acid water), which hurts the plants and animals which are adapted to the Pineland’s very acid waters.

As mentioned earlier, as more acreage is covered by impervious surfaces, runoff rates steadily increase.  Since the water no longer percolates through the soil where nutrients and toxins can be filtered out, this results in more nutrients and pollutants arriving in the area’s lakes, streams and wetlands.  In addition, the water no longer sinks in to recharge the underlying aquifers.

Water Withdrawal: Between 1989 and 1992, an average of 15.5 Mgal/day of groundwater was withdrawn from the aquifers underlying the Pinelands. This water was not returned to the aquifer as recharge since, in this part of NJ, all water treatment plants pump waste water out below the Bay and into the ocean after it is processed. Since more than 90% of the water in Pinelands streams comes from aquifers, rather than from rainfall this declining water levels within the aquifer resulted in a 12% decrease in stream base flow (the amount of water flowing out of the stream at times not immediately after a rainstorm).  That study predicted that the levels of water withdrawal seen in 1992 would double by 2010, which would reduce baseflow of streams in the area by as much as 50%. Clearly, if such withdrawals continue, even a moderate drought may result in significant impacts to natural resources, such as wetlands, streams and lakes drying up.

Invasive Species: Invasive species are organisms that are introduced to a given area outside their original range and cause harm in their new home. Because they have no natural enemies to limit their reproduction, they often spread rapidly, and overgrow and outcompete the native species.  Invasive species are one of the three leading threats to biodiversity today (the others being habitat loss and pollution). It is estimated that the damage done by such species costs the US $137 billion annually.

 When a habitat like the Pinelands is stressed by pollution, warming or other such things, that community becomes more unable to defend itself from invasion by plants not usually found there, some of which may be invasive.  New Jersey does not have a formal, published list of invasive species, but it is estimated that there are more than 1000 species of non-indigenous plants alone present in the state, and many more animals, fungi etc.  Not all non-indigenous (aka "exotic") species are invasive.  However, several of those that are have strong effects on the Pinelands. For example, the invasive purple loosestrife (initially planted as a garden plant for its pretty purple flowers) jeopardizes wetlands by forming dense monocultures along stream banks that replace native vegetation and alter drainage patterns.  Its rapid growth and heavy seed production make it a threat to biological diversity within almost all of the Pinelands wetlands.  

Similarly, Eurasian Watermilfoil (which is a common plant in freshwater aquariums, which is probably how it first entered US waterways in the early to mid 20th century) and Curly Pondweed (a European pondweed which was probably initially deliberately introduced as a “pond oxygenator” but which rapidly spread on its own once it was here) have greatly impacted lakes in the Pinelands and elsewhere in New Jersey. Both species start growing earlier in the season than native flora, resulting in the formation of dense beds and canopies that over-grow and out-compete native plants. Eurasian Watermilfoil is very tolerant of pollution and readily establishes itself in disturbed areas from which native plants have disappeared while Curly Pondweed prefers the more alkaline, nutrient rich waters often characteristic of wetlands impacted by agriculture. 

As mentioned earlier, upland pine barrens communities are adapted to the frequent occurrence of wildfires.  As people have moved in to the pinelands, fire suppression (where fires are put out before they can burn far) is often used to prevent loss of property or farmlands. In such uplands, fire suppression is having strong impacts on species composition, since plants that are not native to the system (because they are not fire-adapted) can now invade and out-compete the native plants.  Moreover, when fires do occur it has been much longer since the last fire than it would normally have been in the past, and so a lot of dead plant material, branches etc. has built up, which then means that the fires are much hotter and burn longer than they would have, had humans not suppressed previous fires.  Such long burning, and intense fires exceed even the Pine Barrens species’ fire tolerances, and everything dies, opening up the entire system to colonization by both native and non-native plants in the future. Among the non-native (aka exotic invasives) that are found in these upland systems, several species present a particular threat to the Pine Barrens species: Japanese stilt grass, Japanese barberry and Japanese honeysuckle (are you sensing a pattern here?  It turns out Japan’s climate is very similar to New Jersey’s so species from there seem to be particular problems in this State).  

Japanese stiltgrass was accidentally introduced to Tennessee in the early 1900s and has spread rapidly throughout the Eastern US from there. It is especially well adapted to low light conditions, so it’s common on the forest floors of the Pinelands. Wherever it grows, it forms large patches that displace native species that are not able to compete with it. Similarly, Japanese barberry, which was first deliberately imported for planting as an ornamental plant and subsequently escaped and spread widely throughout the US.  Like stilt grass it is highly shade tolerant, so it can grow well on the floor of even relatively dense forests, where it forms dense stands that crowd out native species.  Since these species are unfamiliar to native animals, few of them will eat these plants or use them as habitat. Indeed, in places like the Pinelands where white-tail deer are abundant, the deer actually help these species’ invasion by feeding on native plants and avoiding the unfamiliar stiltgrass and barberries. Both stiltgrass and barberry change soil chemistry and pH in ways that make that soil less suitable to the growth of the acid-loving pinelands species. All of these changes thus negatively affect both the plants and the animals and other inhabitants of the Pinelands.


Author Louise Wootton, Ph.D.    Last updated January, 2010.

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