by Russell Burke and Laura Francoeur -
JBTR
About Jack Berlin
About Prizm Share
terrapins
airport
jamaica
jfk
nesting
bay
number
by Russell Burke and Laura Francoeur -
JBTR
About Jack Berlin
About Prizm Share
terrapins
airport
jamaica
jfk
nesting
bay
number
CLEARED FOR TAKEOFF by Russell Burke and Laura Francoeur Taxiing to takeoff, a Boeing 747 weighs 875,000 pounds. Searching for a place to lay her eggs, a female Diamondback Terrapin weighs 18 ounces. What happens when the two meet? I was working on lizards in Rome in June 2009 when my email account started filling up with messages from my friends that something was happening with the Diamondback Terrapins (Malaclemys terrapin) at my Jamaica Bay, N.Y., field site. Terrapins had made the local, national and international news when, for the first time, terrapins swarmed out of the bay, invaded John F. Kennedy Airport in New York City, and blocked runways for hours. The stories were wild - newscasters loved the cute story of slow-moving turtles bringing the airport to a halt. News writers scrambled for information about what was going on, and their reports got pretty ridiculous. There were some incredibly funny animated re-enactments, and apparently terrapin photographs were in short supply because at least five other species were depicted in articles about the invasion. But the reality was a pretty serious problem, because terrapins, with a somewhat ambiguous legal status in New York, were interrupting commerce at one of the busiest airports in the world. Businesses of that size tend to have their own rules and special concerns about conservation and publicity, and this invasion was a serious issue for the JFK authorities. Diamondback Terrapins are one of those unusual turtle species that live in brackish water, not as salty as ocean water or as salt-free as freshwater. Terrapins live in saltmarshes and mangrove swamps hugging the U.S. Atlantic and Gulf coasts. They are closely related to Map Turtles (Graptemys), and like Map Turtles they have extreme sexual dimorphism; females grow up to 11 inches carapace length and can be twice as big as males. They mostly eat snails, crabs and clams, but we have found lots of plant material in the Jamaica Bay terrapin diets as welL Terrapins have relatively small home ranges, and females return to the same sites to nest year after year. 111 Afew hundred years ago terrapin populations were enormous all along the shallow coa tal waters of the eastern United States, living among the vast oyster reefs, and serving as important food for Native Americans for millennia. The word "terrapin" appears to be of Algonquian origin meaning "edible turtle:' Terrapins were so abundant in the 1700s that they were a monotonously common food for servants and slaves; they regularly clogged the nets of fishermen. They were still a common component of humble laborers' diets into the mid-1800s, when, due to a change in culinary fashions, terrapins also became high cuisine. The important distinction was that upper-class terrapin dishes were prepared with fine wines and other expensive ingredients. Large- scale terrapin harvests for commercial markets sprang up to feed the enormous demand from the urban populations in big cities. In 1884 Frederick True, reporting to the Commissioner of Fisheries, wrote, "[Terrapin] is also sold in large numbers in Baltimore, Washington, New York, Boston, Chicago, Pittsburg, Cincinnati, Saint Louis, and many other cities:' In New York City, terrapin soup made from terrapin muscle, viscera, heart and liver, as well as eggs was extremely popular. Famous Americans from George Washington to John Adams to Samuel Clemens loved terrapin. The terrapins for markets came nearly entirely from wild populations, and "Long Islands;' "Delawares" and "Chesapeakes" were highly favored. In New York, terrapins occurred in the marshes around Long Island and the lower Hudson River, all with easy access to the mat:kets of New York City. Terrapins were so beavily barye ted that they were hunted nearlyto extinction. fortunately, 111 the early 1.900s, the terrapin soup fad pas ed, and the harvest dropped considerably. Many terrapin populations managed a partial comeback Then as the 20th century went 011, large- scale coastal urban development au ed massive habitat losses. Wide-scale diking, dredging and filling of urban saltmarshes became common around cities with the advent of heavy machinery. What remained of these marshes became badly polluted. Four of the five states (Florida, Louisiana, New Jersey and Texas) with the highest levels of saltmarsh loss are within the terrapin range, and the coastlines of these four states together comprise two-thirds of terrapin range. Three of the five largest cities in the United States, New York City, Houston, and Philadelphia, are located on estuaries within terrapin range. MARYLAND DIAMONDBACK TERRAPIN SOUP 112 THE TORTOISE' 2014 Serves B to 10 1 Btick butler 2 lablespoons flour 1 qlJiJrt fresh ",ilk salt and pep"er 6 hard-boiled egg~, sep- arated 3 terrapins, 5 to 7 inches in length (2 small cans may be ."bstituted) ~ pint thick cream ~ cup sherry wine ( op- tional, 1o be palled after soup I. 8erved) IF Melt l'lll! hutler in good-Sized suucepan, blend in the flour, thcn nud the milk, snit and pepp r and the hnrd-boiled egg whites wltldt have been (:hoppeJ fine, then add the ter- l"apin mcat (rw preI nrution c::c:: uhovc) as is. Mnsh the egg j'!~!k!.i u:~d "dd ~~in:ii i.u iln:: suup Inixture. 5imme-r until thiak. Theil add Ihe tIlick ureom. Serve hol. When soup has h(:en scrveu, pass slocl'I'y win to be ndded by individual. Or just hi fore erVing. l:I l:lIp of good sherry will can be mixed in the SOllp. ~('rylulld hcul ell biscuits (p ge 105) ure 8 delicious uudition ttl th s ~ieh soup course. Or salUne crackers may be served. -- I .. __ . -' - .~---------~ A female Diamondback Terrapin on a runway at John F. Kennedy International Airport. My study site in Jamaica Bay is no exception - houses and highways and shopping malls now stand on what llsed to be saltmarshes, and JFK Airport itself is built on former marshland. Jamaica Bay is a 17,300-acre, highly urbanized estuary, completely within the political boundaries of New York City. The Manhattan skyline, including the Empire State Building and the new Freedom Tower, is always in the background. The bay is heavily influenced by New York City, of course - it is badly polluted, much of the saltmarsh has been converted to uplands or just removed, marsh loss continues, and the once abundant oyster beds are long gone, replaced by a mucky bottom. My students and I had been studying terrapins in Jamaica Bay since 1998. We have always focused our work on Rulers Bar, Jamaica Bay's 114 TH E TORTOISE' 2 014 ' ," . - - . largest island, which is centrally located and easily accessible by car, bus or even subway. We focused on the females that come ashore to nest in June and July. We already knew a lot about them when the airport story broke. We had felt comfortable mostly ignoring terrapin nesting on the shorelines and the other islands because the survey we did in 2000 to 200 1 showed that there was much less nesting there. In fact, 98 percent of the Jamaica Bay terrapin nesting occurred on Rulers Bar. The east side of the Jamaica Bay shoreline is dominated by JFK Airport, but we mostly ignored it because access was difficult, and we were told there were few terrapins over there anyway. At Rulers Bar we measure and mark each terrapin, injecting each of the 1,200 (so far) terrapins with a PIT tag for unique and permanent (above) Baltimore, Maryland; Houston, Texas; Miami, Florida; New Orleans, Louisiana; New York City, New York; and Philadelphia, Pennsylvania were built on estuaries that were once Diamondback Terrapin habitat. (below) This is what pristine Diamondback Terrapin habitat looks like. 113 JFK is notthe only airport that has endangered reptiles. This airport inhabitant was most likely a San Francisco Garter Snake (Thamnophis sirtalis tetrataenia). De- scribed by the late Robert Stebbins as "the most beautiful serpent in North America," it is also one of the rarest. Confined to a small part of the lower San Fran- cisco Peninsula, it is listed as Endangered. Federal law requires airports 10 keep wildlife off runw;;ays and prn-enled Lhe pilot (rom lUJUling over the snake, "'n lhis case, il'l out of Ml abund20Cc of caution. but it is a federal mandale.~ the spokeunan said ·You don't wanl wildlife or debri..'l on the runw.lIy.It'& nol agreeable 10 the safe opcralionoflhcaircrarl w 1111" ~nake was spoiled. likely by crew, ncar the edge of the runway, he said 115 '. identification. We have measured nesting success, clutch sizes, temperature sex determination, growth rates, parasites and clutch frequencies. We followed hatchling movements, nesting forays and changes in diets over years. We have learned a lot about their predators, mostly raccoons and Norway rats, which eat terrapin eggs and hatchlings. We have documented a decline in the number of terrapin nests from a high of 2,040 nests per year in the beginning through a gradual decline to about 1,032 nests per year now. But, surprisingly, the number of nesting females has stayed pretty constant, so some are laying fewer clutches. At the same time, clutch size has increased and the eggs have gotten bigger. These are the sorts of strange things you only can find with long-term studies; I expect sorting this out will take many more years. So with a decade of study behind me I thought I understood the basics of terrapin biology in Jamaica Bay. Instead, in that summer of 2009 I learned from the newspapers that large numbers of terrapins were nesting in an area where I thought few even existed. Airport personnel and news reporters came to me expecting answers, but there was little I could tell them. Certainly the terrapins were on land looking for nesting sites, but why all of a sudden were there terrapins where they hadn't been before? 116 THE TORTOISE' 2014 Some background on the airport might help. JFK Airport construction was started in 1942, on the site of an old golf course and a lot of saltmarsh. Eventually, 5,000 acres ofJamaica Bay saltmarsh was covered with solid fill. Runway 4 (originally 7,900 feet long) opened June 1949, and was extended (to 11,500) out into Jamaica Bay in the late 1960s. The runway ends on JoCo Marsh, which is the largest and healthiest saltmarsh island remaining in Jamaica Bay. The first question was whether there really were a lot of terrapins at JFK, or whether a small number were having a big impact. We still don't have an estimate of the size of the JFK population, however, in 2011 during a three-hour period, 198 terrapins were captured on land at the airport. In comparison, at our Rulers Bar study site where we estimate 1,000 female terrapins nest annually, we encounter 45 terrapins on a peak nesting day. This implies that the JFK Airport population is larger, maybe much larger. Where did all these terrapins come from? Maybe they were there all along, and 2009 was just the first year they were noticed. Like many major airports, JFK has a full-time team of wildlife biologists who have traditionally focused their attention on bird and mammal hazards to aircraft safety. They are required by Federal Aviation Administration regulations to report many kinds of wildlife interactions. They noted, for example, that terrapins nested in small numbers on the airport's margins since at least the 1990s. Terrapins were first officially reported on JFK Airport runways in 2000; several were reported killed annually since then. More recently, public attention and traffic disruption on the runways caused them to begin monitoring the terrapin population, and they have reported dramatic increases in airport- terrapin conflicts from 2009 to 2012. So it seems like trained people were in the right place at the right time to have seen terrapins on land in large numbers in the years before the 2009 irruption, and their failure to see many terrapins probably means the number of terrapins in those days was small. Perhaps terrapins from elsewhere in Jamaica Bay recently moved to JoCo Marsh because of abundant resources there and started using nearby JFK runways for nesting. JFK wildlife biologists have marked 2,426 terrapins to date, scanned each one first for our microchips and have found none. Given the large numbers of terrapins we've marked at our Rulers Bar site, it seems unlikely that we wouldn't be able to detect such a large exodus. We have not detected a decline in the Rulers Bar population. Also, the airport is about 2.8 miles east of Rulers Bar, which is farther than terrapins normally roam. Finally, the airport terrapin population might have taken off in the last 10 years, perhaps due to a drop in egg predation by their main nest predator, raccoons. We consider this the most likely explanation, although we do not know why the raccoon population would have decreased then. The terrapins in the JFK population are smaller, and appear younger, than those from the Rulers Bar population, consistent with the hypothesis that they are newly maturing individuals. JFK wildlife biologists brought in Dr. Roger Wood and tapped his knowledge on the latest techniques for keeping terrapins off roadways in southern New Jersey. In 2012 airport personnel experimented with corrugated plastic pipe to make flexible temporary barriers to keep terrapins off runways, and in 2013 they expanded these barriers along much of Runway 4, the most problematic site. This barrier has been pretty successful in keeping the troublesome terrapins out of the news. But there are forces greater than a charging 747. Tropical Storm Irene hit in August 2011 and Superstorm Sandy hammered through in October 2012. Irene hit in the middle of terrapin hatchling season, and numerous terrapin nests were washed away. Sandy slammed into Jamaica Bay at high tide bringing dangerous high winds and severe flooding. I spent a very nervous night because I live less than a mile from the ocean myself. Around me communities were devastated, and the amount of debris and contaminants in the water was unbelievable. Since Sandy hit in October, the terrapin nesting season was well over and terrapins were near hibernation. During the night I worried that nests were washing away, terrapins were being injured from storm tossing and killed by being buried in sediment or debris. If many adults were killed, it would take a very long time for the population to recover because there would be little reproduction until surviving youngsters reached breeding age. This was an unpleasant prospect. Within a few days after Sandy, however, we were delighted to see that the saltmarshes had behaved as they are supposed to - most had survived with little damage. Even newly planted marsh restoration sites were in good shape. As I walked the nesting area a week later, it looked different in a way that was hard to identify at first - then I realized that the grass and shrubs and trees were all still there, but all the leaf litter was gone. We didn't know what to expect when the nesting season came around in June 2013 - would our girls return? And we were again delighted to see a normal nesting season in almost every way. The only blemish was several terrapins (from both Ruler's Bar and JFK) with severe shell damage, which looked like chemical burns. I suspect that they were trapped for some time near some caustic chemicals, but they did survive whatever was thrown at them, and this year we see lots of healed shells. Everyone knows that the inhabitants of New York City are a tough bunch. Our marshes and terrapins are no exception. And like many New Yorkers, the terrapins know how to draw attention to themselves, even if it means taking on an airport. So there is hope - we've watched as some saltmarshes have been restored and pollution levels have decreased. There is a new plan to reduce nitrogen discharge, and oyster reintroductions are being planned. And Jamaica Bay still has a very impressive number of terrapins. * 117 "