Sunday, March 02, 2008

Mermaids and Manatees in New Jersey?

Interview with local biologist, Dr. Louise Wootton

Mermaids, Ambassadors from Sea to Sea just returned from a one-week mini-tour of New Jersey. I am grateful to Dr. Louise Wootton, Associate Professor of Biology at Georgian Court University, who hosted the mini-tour and shared her knowledge of Mermaids, Manatees, and coastal resources in New Jersey.

New Jersey is one of the few places, outside the tropics, where mermaid legends overlap with modern manatee sightings. Legend has it that in 1869, two local fishermen caught a mermaid in Barnegat Bay, near the Tom's River inlet! According to the local news article in the Port Jervis Evening Gazette, the captors became "hugely frightened" and allowed the creature to escape!

During the educational outreach expedition, events were held at Rutgers University, Georgian Court University, Wetlands Institute, and Brookdale Community College. Many thanks to Asbury Park Press and Press of Atlantic City for covering these events. To book events in your area, contact caryn@sirenian.org.

Caryn: Louise, the summer we met at Horn Point Marine Lab, Chessie, the Travelin' Manatee, made his first documented migration from Florida to Rhode Island and back, passing by the New Jersey Coast twice. I understand that he might have been sighted since then and that there was another sighting of a female manatee here in 1998. Can you tell me any more about the manatees that have used the coastal waters of New Jersey during summer months?

Louise: We've had several manatee visitors in NJ in recent years. As you mentioned after visiting the Chesapeake Bay in 1994, Chessie visited NJ on his way to Rhode Island in 1995. He came north again in the following years, reaching Virginia several times, but has not been sighted in NJ again. A different, unidentified, manatee who was dubbed "Tappie" (because he was seen swimming in the area under the Tapan Zee Bridge in New York) visited the area in 1998. Most recently, in July of 2006 another manatee spent several days around the entrance to the Barnegat Bay. He was then seen in New York where he swam up the Hudson quite a ways. He then set off northward, ending up in Falmouth, Massachusetts a few weeks later, beating Chessie's record for the furthest North that a Manatee has been observed in US waters, before returning south again under his own steam.

Caryn: We are here at Barnegat Bay Lighthouse, looking north up the Bay. As manatees travel along the coast, we know they need access to resources such as fresh water, warm water, and seagrass. What resources might they find in Barnegat Bay?

Louise: Well the Barnegat Bay is a very shallow lagoonal estuary that is protected by a series of sandspits and barrier islands, so it warms up nicely in the summer time. In addition, the Oyster Creek nuclear power station on the shore of the Bay lacks cooling towers, so it draws water directly from the Bay to cool its reactors, and returns that water to canals that flow into the Bay. As a result there are areas of water in the Bay that are warm year round, though manatees don't seem to have discovered them yet. A number of rivers flow into the Bay, so those would be one source of freshwater. In addition, groundwater from a number of aquifers empties into the bottom of the Bay and in the nearshore region of the Jersey coast, and these underwater seeps would also form another possible source of drinking water for visiting m anatees. In terms of food, the most common seagrass in the Bay is eelgrass which grows particularly well in the shallow "flank" areas of the Bay, especially near the inlets and on the eastern side of the Bay. A little further up (where its a little less salty) we see widgeon grass, especially on the Western shores of the Bay. Finally, in the lowest salinity areas of the Northern Bay we see beds of sago pondweed.

Caryn: I understand that the New Jersey coast is renowned for marine resources. What kinds of plants and animals live in this area?

Louise: In the winter, harbor and grey seals often visit New Jersey's shores, whereas pods of dolphin are common visitors in the summer. We also see a wide variety of seabirds, including gannet, black skimmers, piping plover, a variety of tern species including the endangered "least tern" as well as lots more common species like gulls, herons and egrets. In recent years we have also started to see brown pelicans as relatively common summer vis itors to our shores. Under the water, blue crabs, flounder, weakfish and menhaden are relatively common, and clams like quahog and blue mussels are also still quite common. Bay scallops that used to be quite common in the area are now relatively rare, whereas the much less popular sea-nettle jellyfish have been increasing in abundance rapidly in recent years. Diamondback terrapins used to be so common in the Bay that they were served so often as food to slaves and servants that (like manatee in the south) a law had to be passed limiting the frequency with which masters could make their slaves eat these foods. These terrapins are still found within the Barnegat Bay today, but they are now so rare that they are a candidate for endangered species status. Above water, the Bay is increasingly being surrounded by dense human populations. However, some areas of relatively pristine sand dune are still found especially along the shores of Island Beach State Park on the Bay's Eastern Shore. These dune ecosystems are home to plants like American beachgrass, seaside goldenrod and beach pea. Behind those dunes is a unique maritime forest where you'll find red cedar, American holly, bayberry and beach plum trees among others. On the Bay's Western shore is another unique ecosystem: the New Jersey Pine Barrens. This low nutrient, and high acid hab itat is characterized by pitch pines and a variety of oak trees as well as a bunch of interesting smaller plants like pitcher plants, sundews and another endangered species: swamp pink.The highly tannic waters of the rivers and streams draining this area means that water on the Western shores of the Bay often tends to have a distinctly brown color.

Caryn: Are there any threats to the coastal ecosystem here in NJ?

Louise: Oh boy, are there ever! 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 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. Trace metals like arsenic, copper, lead and mercury and zinc enter the Bay 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. 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. However, probably the biggest problem in the Bay is eutrophication: the addition of excess nutrients. Over 450,000 people live within the Barnegat Bay watershed year round, 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. These nutrients stimulate phytoplankton growth which then shades the seagrasses and limits the depth to which they can grow in the Bay. Once they die they start to decompose which can cause hypoxia or anoxia, even in the relatively shallow waters of the system. This can kill any animals in the water, especially those living in or on the bottom like quahogs and mussels, which can 't move away. For example, 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.

Caryn: Tell me more about your personal research and other activities along the NJ coast.

Louise: My own research has mostly focused on the problems caused by invasive species in New Jersey's coastal ecosystems. Acre for acre, coastal dunes are the most valuable ecosystem in New Jersey, serving to protect the communities behind them from flooding during storm as well creating a reservoir of sand for our beaches. When exotic species invade the dunes they may change those ecosystems so that they no don't do these things nearly as well. In addition, the invasive organisms may also not provide the necessary food or habitat for the other organisms which live in or around the dunes. My research currently focuses on two closely related species of sedge. Carex kobomugi, the Asiatic Sand Sedge, and Carex macrocephala, the large he aded sedge. As well as working to provide an inventory of the areas affected by these species, we are working to understand how they spread, and what their effects are on the plants and animals that are usually found in the coastal dune ecosystem. We are also working on building public awareness of the problems caused by invasive species by creating curriculum materials for use in local schools. Students in my lab have also been studying chemicals called polybrominated diphenyl ethers (PBDEs) which have been dubbed “the PCBs of the 21st century”. Commonly used as flam e-retardants, PBDEs are found in a wide variety of products including furniture and electronic equipment. PBDE residues have been found in the tissues of marine and terrestrial species around the globe, and to have major impacts on animal and human health. For example, PBDEs are linked to decreased eggshell thickness in peregrine falcons and decreased bone densities in polar bears. PBDEs have also been found to be potent thyroid disruptors, have been implicated in the development of learning disabilities in mice and are likely carcinogens. PBDE concentrations in human tissues have increased about 100 fold over the past 30 years, with concentrations in people from the United States being about 20 times higher than in people from Europe, where there has been stronger regulatory control over PBDE manufacture and use.Concentrations of PBDEs in New Jersey’s Coastal Ecosystems are poorly known, so my students and I are working with a colleague who is an environmental chemist to develop the necessary methods to measure these chemicals so that we can monitor levels of PBDEs in sediment, water and biota within the Barnegat Bay in the future.

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