Subject: New England Aquarium Seabits 2.6 (fwd)

mike williamson (
Fri, 5 Jun 1998 10:42:59 -0400 (EDT)

Date: Fri, 5 Jun 1998 09:50:39 -0400
To: Seabits <>
Subject: New England Aquarium Seabits 2.6

New England Aquarium Monthly e-mail Newsletter
Volume 2, Issue 6, June, 1998
Copyright, New England Aquarium, 1998.
June brings news of happenings along the coast of Delaware Bay along the
New Jersey coast, detailing the arrival of horseshoe crabs and red knots.
Locally, we bring news of Myrtle, our own learning turtle.  - Susan
Gedutis, <>.

In this issue:
  Watery Words
   - Horseshoe Crabs: A Decline of the Old Timers?
   - The 10,000-Mile Flight of the Red Knot
   - Aquarium Turtle Recruited for Research Venture
  Kayak with the Aquarium
  Radio Rocks the Fish in June
  June Calendar
  Corrections... No, Virginia, Turtles are Not Mammals.
  Subscribe/Unsubscribe Information
  Contact Us

=-=-= WATERY WORDS =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

"So, the fact is that no serious inventory of marine life has ever been
made... In total, biological surveys have scannded perhaps 5% (and maybe
much less) of the world's oceans."

                                     -- Alfred H. Ausubel
                                        Alfred P. Sloan Foundation

=-=-= STORIES =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
This month's stories:
  1) Horseshoe Crabs: A Decline of the Old Timers?
  2) The 10,000-Mile Flight of the Red Knot
  3) Aquarium Turtle Recruited for Research Venture

------ HORSESHOE CRABS: DECLINE OF THE OLD TIMERS? ------------------------
Special to Seabits by Stefanie Jeruss

Spring is here and the beach beckons. But watch your step because you're
not alone! The beach is also the home of many horseshoe crabs. The warm
spring months bring horseshoe crabs from the deep ocean water to sandy
beaches to reproduce. Some say that because of overfishing, we're seeing
fewer horseshoe crabs these days.

During breeding season, the female horseshoe crab crawls up to the sand and
deposits up to 30 thousand eggs in her nest so they can be fertilized by
the male and covered with sand. When the moon is full and the tide is calm,
larvae (babies) hatch and return to the water to learn the ropes.

The horseshoe crab, or Limulus polyphemus, is not really a crab at all; it
is a distant relative of the spider. Horseshoe crabs live for about 19
years in shallow parts of the Atlantic Ocean between Nova Scotia, Canada
and Yucatan, Mexico. Its body looks like an upside down bowl in the shape
of a horseshoe, with a sharp tail trailing behind. Horseshoe crabs feed on
clams, worms, and other invertebrates and use their legs to grind and crush
their food. As a species, they are 400 million years old, and now
scientists are discovering that horseshoe crabs may help save lives. The
blood of horseshoe crabs can be used to detect poisons that may be present
in both human patients and medical drugs.

"The horseshoe crab enjoys a rather unusual place in nature," wrote Patty
Sturtevant, Ph.D., of the Sarasota Marine Lab, " that, if one
discounts man, it has no known natural enemies."

However, man is creating problems for the horseshoe crab. "The number of
horseshoe crabs on the Delaware Bay beach has declined from an estimated 1
million at the beginning of the decade to about 300,000 last year (1996),"
according to Delaware zoologist Kathy Clark. Many scientists believe this
to be a result of overfishing. In 1996, some 2 million pounds of horseshoe
crabs were caught along the Atlantic coast and used as bait for eels,
whelks and catfish. Worse, female crabs are caught most frequently, and
often before they have a chance to lay their eggs. These events have
devastating effects further up the food chain; migratory birds rely on
horseshoe crab eggs as a main food staple during stopovers on their yearly
flight north.

Luckily, the Atlantic States Marine Fisheries Commission is currently at
work on developing a fisheries management plan for the horseshoe crab, with
public hearings in June and July, and final plan approval slated for
October 1998.

So, the next time you stroll on the beach and admire the water, please look
out for the shelled, spiderlike creature who may be lurking beside you.
Leave it be, and don't disturb its nest, which is filled with green,
pinhead sized eggs.

You can also visit the horseshoe crabs at New England Aquarium's "Edge of
the Sea" tide pool exhibit.

Droplet: The horseshoe crab has blue blood. Its blood contains copper
rather than hemoglobin, the ingredient that gives human blood its red

------ THE 10,000-MILE FLIGHT OF THE RED KNOT -----------------------------
To the red knot, Delaware Bay is a highway rest stop--an important place to
refuel for its annual 10,000 mile journey from the southern tip of South
America to the Arctic. This shorebird's fuel is not burgers and fries,
however. The red knot is looking for a seafood delicacy: horseshoe crab
eggs. In order to make the flight, the red knot must eat, and eat heartily.
At the end of May, enough horseshoe crab eggs cover the beaches of the bay
that in two weeks, a bird can eat enough to double its weight. One knot may
eat up to 135,000 eggs during its Delaware stopover.

The red knot's journey begins in early March on the shores of Patagonia.
There, red knots prepare for their flight by putting on weight at an
astonishing rate. The first stop on the north-bound journey is the
Peninsula Valdez, along the central Argentinean coast. Then they fly to the
coasts of southern Brazil, where they fuel up again. Knots laying over in
southern Brazil may increase their weight by as much as 80 percent when
preparing to fly the eight-day, 7,000 mile stretch to the mid-Atlantic
coast of the United States. "In human terms, this would be equivalent to a
weight increase from 140 to 270 pounds in a month, roughly a rate of four
pounds a day!" writes Brian Harrington in his book, "The Flight of the Red

Evolution has scheduled that red knot arrives in Delaware Bay, in the
extreme southwestern areas of New Jersey, just in time for the horseshoe
crab invasion. So many horseshoe crabs come ashore at that time to lay eggs
that they inadvertently dig up each other's nests, leaving millions of eggs
floating in the lapping waves. These eggs become fodder for the red knot in
an annual banquet that attracts one of the most immense concentrations of
shorebirds--red knots, sanderlings, ruddy turnstones and sandpipers--known
in North America. By early June, once red knots have had their fill, they
begin the final leg of their journey to the breeding grounds of the low
Canadian Arctic. There, they breed, nest and bear young. Within a couple of
months, they begin the journey back south.

No one knows how many red knots exist, but estimates range from about
100,000-200,000 birds. Although their population is relatively healthy, it
is important to protect them to prevent declines. Limiting the horseshoe
crab harvest is a perfect example. There has been a decline in the number
of horseshoe crabs, and thus horseshoe crab eggs, in Delaware Bay. If the
red knots don't have enough to eat, they may not reach their breeding
grounds in the tundra. In response, mid-Atlantic states have put limits on
harvesting horseshoe crabs.

The most important way to protect the red knot and many other migratory
shorebirds is to protect habitats at all of its stopping points from South
America to Canada. On local beaches, that means we should heed signs and
stay out of nesting and resting areas. Shorebirds need this time to rest,
preen their feathers, digest their food and sleep.  Ever notice that after
an active, busy day it seems to take more energy than it's worth to even
get up to change the station on the television? Imagine how it might feel
after having flown thousands of miles. Brian Harrington of the Manomet Bird
Observatory suggests that red knots may use up two thirds of their total
energy just to avoid numerous daily disturbances from passing beach
vehicles, wandering pets and well-meaning picnickers and boaters.

To learn more, we highly recommend Brian Harrington's book, "The Flight of
the Red Knot," published by W.W. Norton and Company. Brian weaves a story
of the life history of the red knot that reads like a novel. Even
non-birders will find the writing graceful and captivating, the science
solid and the photos dramatic.

You can see shorebirds at the New England Aquarium's new Coastal Rhythms:
Creatures on the Edge exhibit.

Droplet: Although the red knot is not closely related to red-breasted
robins, it is sometimes called the beach robin.

By Sue Knapp

Myrtle, a 550-pound, 50ish green sea turtle and long-time New England
Aquarium resident, is playing an instrumental role in an exciting hearing
study. All species of sea turtle are either endangered or threatened, and
little is known about sea turtle hearing. Data gathered in this study will
be used in the ongoing effort to learn more about sea turtles and determine
if human-made sounds in the ocean are detrimental to sea turtles. Oceans
are busier and noisier than ever before. Large ships, for example,
contribute to the din with rumblings that can travel underwater for
hundreds of miles and sound louder than jet planes.

Myrtle's project is the first to test and record hearing capabilities in
sea turtles using "operant conditioning." Operant conditioning, a type of
learning exhibited by all animals, including humans, reinforces behavioral
responses through positive reinforcement--like food. Data obtained through
operant conditioning tends to be more consistent than data gathered through
other methods, such as recording changes in heart rate. Plus, Myrtle is
very responsive and interested in what goes on around her, making her a
perfect candidate to help with this study. Myrtle appears not to be
bothered by all the attention.

To date, Myrtle has learned: -- to come to the dive platform when she hears
two small pipes tapping together underwater, -- to swim to and touch an
underwater speaker when it emits a tone, and finally, -- to return to the
dive platform and receive her fish or squid reward (if she touches the
correct speaker).

In order to fully study her hearing capability, researchers will progress
to presenting Myrtle with a choice of two to four underwater speakers, only
one of which will emit a sound. When she touches the correct speaker, the
sound will stop and Myrtle will return to the platform for a reward. Tones
of various frequencies will be played, and the position of the correct
speaker will change.

Funding for this two-year project comes from an Office of Naval Research
grant totaling $120,000. New England Aquarium collaborators are Dr. Arthur
Popper and Dr. Robert Dooling, both professors at the University of
Maryland in College Park, Maryland. Dr. Popper has extensive experience
studying hearing in fish and dolphins, and the anatomy and physiology of
the auditory system. Dr. Dooling is an authority in behavioral studies of
hearing in animals and has conducted definitive studies of hearing by
birds, and he has also developed several techniques that are now widely
used in animal hearing studies.

At the New England Aquarium, Kathy Streeter, a marine mammal expert with 24
years of training experience, is the principal investigator. "It's been an
education working with Myrtle," says Streeter, "and the project is
challenging. Myrtle is not as agile as a marine mammal, and she moves quite
slowly. I have learned to be patient and to watch carefully for Myrtle's
reactions, which are quite clear.n Based on her work with sea lions and
dolphins, Kathy worked to develop an effective training protocol. Not only
did she have to adapt the training methods to be used with a large sea
turtle, the equipment also needed to be tailored to accommodate the Giant
Ocean Tank exhibit and all the other animals living there."

In the future researchers hope to determine if sounds can be used to help
free-ranging sea turtles avoid fishing nets, a serious threat to turtles in
the wild. The use of sound as an entanglement deterrent has proven
successful with marine mammals (see Nature, August 7, 1997). This project
also complements current work to develop a "Sounds of the Sea" exhibit
which will open at the Aquarium in the spring of 1999. The exhibit will not
only describes the naturally noisy underwater realm, but it will also allow
visitors to experience some of those sounds.

Droplet: Unlike freshwater turtles, sea turtles cannot pull their heads
and legs into their shells.

=-=-= OUT ON THE NET =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
For additional information, you might want to check out the following
websites. Some of these links represent partners in aquatic conservation
and animal husbandry; others are simply resources we think may help you
enrich your perspective on our watery world. By listing these websites, the
New England Aquarium is not automatically endorsing or verifying the
accuracy of their content unless explicitly stated.

Horseshoe Crabs

Red Knot and Shorebirds

Green Sea Turtle

=-=-= KAYAK WITH THE AQUARIUM =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
On June 27, kayak Hingham Harbor with the New England Aquarium. Enjoy the
summer; join a small group led by the New England Aquarium and Maine Island
Kayak Company to experience kayak, the world's fastest growing water
activity. Our kayak trips provide excceptional recreational and educational
expereince. You will leave refreshed and invigorated with a strong sense of
your abilities on the water. Athletic beginners welcome. A great
introductory paddle. We venture past World's end, planned by Frederick Law
Olmsted. It's one fo the most spectacular landscaped areas of open space
with views of the Boston skyline across the harbor.

Includes kayaks, safety equipment, expert instruction and an Aquarium
naturalist. Future trips: July 26 - Charles River, and Aug. 22 - Plum
Island, Ipswich Advanced registration required. $95. 10 a.m. - appx. 4 p.m.
Reccommended for ages 16+. Register by calling (617) 973-6562, or sending
email to <>.

Looking Ahead...
Boston Harbor Island Camping Enjoy the exciting historic sights, sounds and
landmarks of Boston Harbor including panoramic views of the city skyline.
Overnight camping, round-trip water transportation, and guided natural
history walks by Aquarium naturalists. July 18-19 or Aug. 15-16 (Rain date
for both trips: Aug. 22). Camping only: $50 Adults, $45 Children. Camping +
optional food: $75 Adults, $70 Children

Call (617) 973-6562 for more information on trips to the Galapagos, South
Africa, Manitoba, British Columbia and more.

(All trips are subject to change due to circumstances beyond our control.)

=-=-= RADIO ROCKS THE AQUARIUM IN JUNE =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Eagle 93.7 will land on the Aquarium plaza on June 11 from 12-2. Stop by to
hear some of your favorite music from the 70's and 80's and to win some
great prizes. The fun continues on June 18 when the Kiss 108 Traveling
Beach Party takes place at the Aquarium from 12-2. Don't miss your chance
to meet Kiss 108 DJ Skip Kelly who'll be giving away frisbees, t-shirts,
cd's, concert tickets and other prizes.

=-=-= JUNE CALENDAR =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Saturday, June 6, 12:00 P.M. - 4:00 P.M.
Freshwater Fair, Leverett Pond, Jamaica Plain. Celebrate the importance and
beauty of ponds and rivers at the 3rd annual Freshwater Fair. Peer into a
microscope to see some of Leverett Pond's tiniest animal and plant life.
Take a trip back in time to learn of the history of Frederick Law Olmsted's
famous Emerald Necklace. Pitch in to help clean up the pond. Listen to frog
sounds, investigate animal tracks, get your face painted, or try your
hand-- literally--at thumbprint art. Leverett Pond is located on the
Brookline/Bosotn border at the intersection of Route 9 and the Jamaica Way.
Sponsored by the Aquarium, Boston Parks and Recreation Department, the
Brookline Conservation Commission and local school groups. For more
information, call (617) 973-0274 or send e-mail to Heather Tausig at

Sunday, June 7
Breakfast with the Trainers: Catch the training session and enjoy a private
breakfast with the trainers aboard the Discovery. Training session begins
at 9:15 A.M.; continental breakfast follows the session. Recommended for
all ages. Children must be accompanied by an adult. Doors to the Discovery
open at 9:00 A.M. $10.00 per person for members; $15.00 plus admission fee
per person for nonmembers. Call (617) 973-5206 to register.

Saturday, June 13, 10:00 A.M. - 2:00 P.M.
Canoeing the Sudbury River in Concord, MA: Join Aquarium educators to
investigate the sights and sounds of the Sudbury River. With an onshore
safety and boating lesson to start, experience this important freshwater
highway with binoculars, field guides and water testing kits. Participants
should bring their own lunches. Personal canoes may be used. For ages 8 and
older. $20.00 per person for members; $30.00 per person for nonmembers.
Nonmember price does not include Aquarium admission. Call (617) 973-5206 to
register. Directions will be mailed to all registrants.

Saturday, June 20, 9:15 A.M.
Giant Ocean Tank Walk & Talk: Dip into the lives of the inhabitants of the
Aquarium centerpiece, the Giant Ocean Tank. Walk down the helix ramp, from
the surface to the depths. See how the habitat and representative species
change as you delve deeper in the Caribbean coral reef. For ages 6 and
older. Tour fees are $4.00 per person for members. $8.00 per person plus
admission fee for nonmembers. Children must be accompanied by an adult.
Call (617) 973-5206 to register.

Saturday, June 20, 10:00 A.M. - Noon
Tidepool Trek: at Chandler Hovey State Park, Marblehead, MA: With field
guides, microscopes, and magnifying boxes, find out what lives in
tidepools, learn how to identify marine life, and see how these animals
have adapted to live in their turbulent tidal world. For ages 6 and older.
$6.00 per person for members; $12.00 per person for nonmembers. Nonmember
price does not include Aquarium admission. Call (617) 973-5206 to register.
Directions will be mailed to all registrants.

Sunday, June 21
Fathers' Day Harbor Tour: Treat Dad to a special "Science at Sea" excursion
on Boston Harbor. The 90-minute trip departs Central Wharf at 11:00 A.M.
Call (617) 973-5206 for more information.

=-=-= CORRECTIONS =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Yes. You are right! We made an embarassing proofing error. Leatherback
turtles are definitely not mammals, they are big reptiles. Interestingly,
they *are* actually warm-bodied, which helps them survive cold North
Atlantic waters. Everything else about them is reptilian, however.

=-=-= SUBSCRIBE/UNSUBSCRIBE INFORMATION =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
To subscribe to Seabits, either visit <>
OR send e-mail to <>. In the body of your email message
write "subscribe seabits" (without the quotes).

To unsubscribe to Seabits, send email to <>. In the body
of your email message write "unsubscribe seabits" (without the quotes).

=-=-= CONTACT US =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Content questions and comments? Contact Susan Gedutis at <>.

Technical questions and comments? Contact Bruce Wyman at <>.

=-=-= THAT'S ALL FOLKS =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
It's a lovely warm spring in Boston... hope it's pleasant for you, too,
wherever you are!