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. *
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