Conserving the Cape Fear : a semiannual publication of the North Carolina Aquarium at Fort Fisher |
Previous | 1 of 4 | Next |
|
small (250x250 max)
medium (500x500 max)
Large
Extra Large
large ( > 500x500)
Full Resolution
|
This page
All
|
Photo courtesy Mike Suchy ConCservianag ptphe e FeVaoal. III Irsrsue 1 Winter 2005 A semiannual publication of the North Carolina Aquarium at Fort Fisher Conserving the Inside this issue... Managing a Fishery: A Complicated Answer to a Simple Question. P. 2 Turtle Trails: Where Do Our Turtles Go? P. 4 The Butterflies of Ft. Fisher P. 6 Why Do Marine Mammals Strand? P. 8 Conservation Through Appreciation...A Different Approach P. 9 Why Recycle Oyster Shells? P.10 Fisheries Management “A complex answer to a simple question.” By Fritz Rohde Fisheries Biologist NC Division of Marine Fisheries Continued page 3 Catch of the Day: Grouper, porgy and snapper, respectively ( Fritz Rohde) Page 2 What does it take to manage a fishery? This may seem like a simple question, but it is one that requires a complex answer. In the “old” days, it may have been by the seat of your pants or by the “Bell System,” wherein whoever called the most often got the management decisions they wanted. But since the early 1980s for fisheries in the Atlantic Ocean, and since 1997 for our state fisheries, documents called Fishery Management Plans (FMPs for short) are prepared to ensure the long-term viability of these fisheries. These FMPs are developed, with public input, to describe the nature and problems of a fishery and to propose management regulations to conserve the fishery. The goal of an FMP is to prevent overfishing while allowing optimum yield. Overfishing can be defined as harvesting at a rate greater than what will meet the management goal (i.e., sustain the species) while optimum yield can be summed up as the harvest level for a species that achieves the greatest overall benefits, including economic, social, and biological considerations. So, what is needed for an FMP? An FMP contains a great deal of information on the biology of the fish stock (a harvested or managed unit of fish may be a single species or a multi-species complex) and the fishery (recreational and commercial landings, gear, areas fished, and socio-economic data). The Plan identifies the problems in a fishery and proposes management measures (fishing regulations) to correct the problems. One of the key components of a FMP is the stock assessment that describes the conditions or status of the stock. This incorporates as much as possible about the biology of the species in the stock and about the fishery on this stock. The biological information can include the age at which it first spawns, the ages of the fish in the population, how many eggs are produced, and the ratio of females to males. Information on the fishery may include types of gear used, the commercial and recreational landings over a large number of years, the age structure of the fish that are harvested, the fishing effort expended, and the ratio of females to males. Since the goals of an FMP are to prevent overfishing and to rebuild overfished stocks, how are we doing? The first state FMP was approved in 1998 (blue crab). Since then, nine others have been completed (two are still in draft form). “Whether the fishermen or the modelers (scientists) are right is difficult to ascertain. Undoubtedly, the answer lies somewhere in between.” Page 3 Snapper, iced down prior to market. (Fritz Rohde) Commercial fishing is a major industry on our coast. (Fritz Rohde) Given the relatively short period of time involved, it is too soon to tell for most of them but there have been some encouraging signs with the red drum stock and striped bass in Albemarle Sound. On the federal level, the Snapper-Grouper FMP has been around since 1983. It is such a complex fishery (with 73 species being managed in it) that currently the South Atlantic Management Council is undergoing the 13th amendment to the Plan. Previous amendments have established size limits, bag limits and spawning season closures, and have limited or prohibited certain types of fishing gear and reduced the number of commercial fishermen. One idea that has been discussed by the Council for a number of years is Marine Protected Areas where fishing for these species would be off limits. There is disagreement as to how successful the current management measures have been. Many fishermen believe that the regulations have had a positive impact on the fish stocks and they are catching fish at the same rates and sizes as they did years ago. On the other side of the coin are results of computer modeling done by the National Marine Fisheries Service indicating that many of these species are still overfished and that the current regulations will not allow the stocks to recover. Managing a fishery does not have the preciseness present in the other sciences. Whether the fishermen or the modelers are right is difficult to ascertain. Undoubtedly, the answer lies somewhere in between. A complex answer to a simple question. For specific fisheries stock status and other information log on to www.ncfisheries.net Imagine walking along the beach and spotting a live sea turtle, weighing more than 100 pounds, stranded in the surf. Each year North Carolina's Sea Turtle Volunteers are called on to carry sick or injured sea turtles to one of two rehabilitation facilities in the state. Dedicated volunteers staff both the NEST Rehabilitation Facility at the North Carolina Aquarium on Roanoke Island and the Topsail Sea Turtle Hospital located in Topsail Beach. The goal of both programs is to release healthy sea turtles back into the wild. Rehabilitating sea turtles requires long hours, and appropriate husbandry and veterinary care. But watching greens, loggerheads and Kemp's ridleys crawl back into the ocean after spending months in tanks is an incredible reward. For years we wondered whether these animals survived, and where they traveled after release. A study designed to answer these questions, and funded by the Institute of Museum and Library months when water temperature dropped. A second group migrated farther south, along the coasts of South Carolina, Georgia, and as far as Florida. The third group moved offshore into the mid north Atlantic, and over wintered in the warmer waters of the Gulf Stream current. Once coastal water temperature warmed, loggerheads returned north of Cape Hatteras. Some entered the sounds behind the barrier islands, while others continued migrating offshore, one as far north as Maryland. We have yet to determine why a particular sea turtle chooses one pattern over another. Water temperature does appear to be a critical factor in loggerhead migration, with most preferring to remain in waters above 10 C (50 F). Sea turtles can become stranded for many reasons, some of which are human caused. For example, some sea turtles will ingest plastic bags or other pieces of trash thinking they might be food. Contaminants in the water may also sicken sea turtles. “Bogue” surfacing to breathe after having the transmitter attached (Joanne Harcke) Services, has yielded some incredible results. Since September 2003, ten loggerhead sea turtles (Caretta caretta) were released from the NEST Rehabilitation Facility at the Aquarium on Roanoke Island and four loggerheads were released from the Topsail Sea Turtle Hospital, all with satellite transmitters attached to the carapace (upper shell). Biologists from Wildlife Resources Commission used a two-part epoxy resin to securely fasten the transmitters. Each transmitter was programmed to send location coordinates and water temperature data to satellites, which then beamed the information to a receiving station on the ground. Using data collected from a Duke University study on wild-caught loggerheads, we were able to compare the post-release movements of our rehabilitated sea turtles. Regardless of whether they were wild-caught or rehabilitated, three patterns emerged. One group of loggerheads remained in the coastal waters of North Carolina, migrating south of Cape Hatteras in the winter Where in the World Do Our Sea Turtles Go? TURTLE TRAI By Joanne Harcke LS Conservation and Research Coordinator North Carolina Aquarium at Ft. Fisher Continued page 5 Page 4 All species of sea turtle must surface to breathe, which makes them vulnerable to boat strikes. With proper care, we now know, these animals can be successfully rehabilitated and released back to the wild. But rehabilitation takes time and money; therefore preventing sea turtle strandings is a critical component of saving these endangered and threatened species. Picking up trash, watching from a safe distance, always disposing of used fishing equipment properly, and improving water quality are actions each of us can take to help preserve and protect sea turtles. So, the next time you're walking along the beach looking out across the ocean, consider the amazing journey of the loggerhead. And while we have learned the Transmitter attached, “Obie's” released at Topsail Beach (Jacob Rudolph) answers to some questions, many others are waiting to be discovered. http://www.ncaquariums.com/turtletrails/ For more information on the Turtle Trails Project, log on to: Page 5 A visit to the North Carolina Aquarium at Fort Fisher just wouldn't be complete without a stroll through the Memorial Garden. There are native trees and shrubs, salt-tolerant landscape plants, colorful flowerbeds, a birding deck and beautiful memorial sculptures. There are also butterflies - lots of butterflies! Late summer and early autumn are the perfect time for butterfly watching. Spring caterpillars have become adults and migrants move through the area, coming from both north and south. The highest diversity of species occurs in September. We began preparing our gardens for butterflies one year ago, by seeding copious amounts of curly parsley, dill and fennel all host plants for several species of butterflies, most notably the swallowtails (we have six species that occur along the coast here). We also grew garden varieties of cabbage, carrots, broccoli, and alfalfa (from sprouts sold in supermarkets!). All these easy-to-grow plants attract adult butterflies for the purpose of egg laying. Perhaps the best-known example of a butterfly host plant is the milkweed. These moisture-loving perennials (there are several species) are the sole host plants for monarch (Danaus plexippus) and queen (D. gilippus) butterflies. We seeded milkweed in mid-summer and had monarchs fluttering around the young plants before we got them planted! Of course, all of our native butterflies are adapted to native plant species of the region. It ought to be taken into consideration that as land is cleared for development and non-native landscape plants replace natives, many species of butterflies (and other animals) lose what is necessary for their reproduction. Some examples may be found in some of our largest and showiest butterflies. The host plants of the spicebush swallowtail (Papilio troilus) include spicebush, a wetland plant, and sassafras, a common shrub in upland woods and edges, which are routinely clear-cut. Another upland shrub, the paw-paw, is host plant to the stunning zebra swallowtail (Eurytides marcellus). And a true southern beauty, the palamedes swallowtail (Pterourus palamedes), is a creature of the wetlands. The larvae feed on red bay, sweet bay and, again, sassafras. There The Butterflies Of Fort Fisher By Melanie Doyle Horticulturist North Carolina Aquarium at Fort Fisher are almost 190 species of butterflies occurring in North Carolina, and many of those are found only along the coast, some just in our southeastern region. A few species seen here in the fall actually have migrated north to feed. Many of the beautiful pale yellow sulphur species (where the term “butter” fly may have come from) move north in late summer, creating eye-catching “flocks” of flittering yellow above open fields and gardens. The large cloudless sulphur (Phoebis sennae) comes our way from the tropics, South America, the Caribbean, and southern Florida. It isn't understood why these animals come so far north in the fall (as far as New York!), and why they Page 6 Longtail skipper (Dick Roberts) Monarch butterfly (Dick Roberts) Continued page 7 perish with the onset of winter, not returning south again. But while here, they feed on the nectar of almost any flower they find (here at the Aquarium they love our tropical hibiscus and lantana). So far this summer (since mid-August), we have identified, with confidence, thirteen species of butterflies on the Aquarium grounds. Many, however, are small and elusive and will require capturing in order to identify to the species level. The skippers, hair-streaks and satyrs are only about one inch long, and primarily brown-- much more difficult to identify than the larger, colorful species. While we will continue watching, identifying and enjoying our butterflies over the next few weeks, preparations are already underway for next year. We continue to add both host and nectar plants to the gardens, as well as a feeding station in order to attract those species (such as the red admiral) that do not feed on nectar, but instead on sap, carrion and rotting fruit. Also, the limitation of insecticides is very important as any broad-spectrum chemical sprayed for insect control readily affects butterflies. Remember, in addition to being beautiful residents and visitors in our gardens, butterflies are a good indicator of the overall health of our surrounding environments! Plants for adult butterflies to lay eggs To attract migrating butterflies Hibiscus Lantana Pentas Gilardia Echinacea Curly parsley (lots) Garden varieties of: cabbage, carrots, broccoli, and alfalfa Milkweed Spicebush Sassafras Paw-paw Sweet bay Red bay Sassafras Not all la ts listed p n a e native. se r U nat e plant w en iv s h ossible p . Cut out the list when you’re ready to shop. Page 7 Monarch butterfly (Dick Roberts) Since Aristotle’s time, around 350 B.C., people have been attempting to discover why marine mammals “strand.” A stranding is defined as the beaching, either alive or dead, of a marine mammal. Marine mammals include whales, dolphins, seals, sea lions, walruses, sea otters, polar bears and others. Focused scientific studies on strandings really began in the 1970s (Malakoff 2001). Some stranding of marine mammals can be controversial, and there is often no clear evidence as to why these animals come ashore. Most often, marine mammals strand as single individuals (National Marine Life Center). Occasionally mass strandings, defined as three or more individuals, occur. In some cases up to 400 individuals have stranded on the beach at one time. In the United States, about 3,000 to 4,000 marine mammals strand per year. About 75 percent of the time, these animals are already dead when they wash ashore (Malakoff 2001). Strandings can have many potential causes or contributing factors, some natural and some human-related. For single strandings, these include: 1. health complications associated with pregnancy 2. separation of a dependent calf from its mother 3. predation by sharks or killer whales, 4. natural biotoxins (e.g., red tide poisoning) 5. disease, parasitism, and old age ingestion of trash 6. entanglement in fishing gear 7. vessel strikes (Malakoff 2001, National Marine Fisheries Service, National Marine Life Center). For mass strandings, hypotheses for causes include: 1. social cohesion, (If an individual in the group becomes ill and strands, the rest of the pod will follow) 2. geomagnetic disturbances that may cause navigational errors, 3. pursuit of prey too close to shore, 4. barriers to, or disturbances in, echolocation in shallow water 5. Complex geographic oceanic conditions such as abnormally high or low tides (Malakoff 2001, National Marine Fisheries Service, National Marine Life Center). Live marine mammal strandings represent the most difficult event faced by stranding-response personnel. The decision to euthanize or release/rehabilitate is always done in consultation with a veterinarian. Most often, the decision for a single stranded individual is to euthanize, based upon the animal’s health condition. Malakoff (2001) stated, “There must be both a humane society dealing with the welfare of stranded animals and an objective institution collecting scientific data.” Guidelines have been set up as to when it is proper to euthanize an animal or when to release it back into the wild. “Euthanasia shall only be performed by an attending veterinarian or by a person acting under the direct supervision of an attending veterinarian” (Marine Mammal Stranding Agreement 2004). Scientists and veterinarians try to learn as much as possible from each stranding. Tissue samples collected from dead stranded animals can not only help determine the cause of death, but also aid in discoveries about anatomy, ecology, and evolution. The life histories of some marine mammals are known exclusively through stranding data. They also tell us information about their diets, how many young they have, and how old they are when they first reproduce (Malakoff 2001, National Marine Fisheries Service). Why Marine Mammals Strand By Justin Perrault Marine Science Student University of North Carolina at Wilmington Works Cited: Malakoff, D. Marine Mammals: Why do Marine Mammals Strand? Science 2001 293: 1755. Marine Mammal Stranding Agreement Between National Marine Fisheries Service of the National Oceanic and Atmospheric Administration Department of Commerce and [Stranding Network Organization]. Article I. General Authority. 2004. [Available from the Internet.] URL:<http://www.nmfs.noaa.gov/pr/pdfs/health/stranding_agreeme nt_template.pdf>. National Marine Fisheries Service. NOAA Fisheries Frequently Asked Questions about Marine Mammal Strandings. [Available from the Internet.] URL:<http://www/nmfs.noaa.gov/pr/health/faq.htm>. National Marine Life Center- Buzzards Bay, Massachusetts. Marine Animal Stranding. [Available from the Internet.] Stranding.html>. Page 8 Rare Blainsville beaked whale strands on Kure Beach in 2004. Stranding Team educates onlookers as they evaluate the whale.(File photo) Whether photographs of serene coastal landscapes, the explosion of colors captured on film at an underwater reef, the fluidity of a jellyfish ballet, or the strange chorus from a symphony of swamp characters, art gives us opportunities to appreciate aquatic habitats in ways the superficial experiences of our everyday lives cannot. Aquatic-themed photographs, linoleum prints and kids’ art have touched numerous visitors at the North Carolina Aquarium at Ft. Fisher. Echoes of “Ooh!,” “Aahh!,” and “Wow!” fill the aquarium’s Spadefish Gallery daily. Talk with people you know who scuba dive on the world’s reefs or trek the remote coastal wilderness. Many have been inspired and driven from a single spark, often from some form of art: a picture, a story, a song or even an animated Disney film. Ask a dolphin scientist how they were inspired and it’s a sure bet “Flipper” or “The Adventures of Jacques Cousteau” are mentioned in the mix. And who doesn’t care about clownfish and tropical reefs after seeing “Finding Nemo”? So, if you want to help protect our natural resources, try seeding appreciation through art; view conservation as a link between art, science, the heart, and positive action. Conservation through Appreciation ...a different approach By Jackie Harris Educator North Carolina Aquarium at Fort Fisher Page 9 Lookdowns at the North Carolina Aquarium at Fort Fisher (file photo) Why Recycle Oyster Shells? By Jackie Harris Educator North Carolina Aquariums Oyster Hatchery Team Early seafarers once shunned oysters because the reefs they created caused navigational hazards. However, these same people eventually recognized oysters as a culinary delicacy -- a delicacy whose population currently comprises just one percent of its historical mass. And those treacherous reefs? If early settlers had only known the far-reaching benefits of an oyster reef, they might have been a little more patient. Commercial oyster harvesting on the east coast of the United States began in the 1800s. Initially, oysters were harvested by hand or rake. Ingenuity quickly led to the invention of a mechanical dredge, introduced to the industry in the late 1800s. At that time, annual oyster harvests peaked at 1.8 million bushels per year. In 2000, less than 40,000 bushels were harvested. This dramatic decline in oyster harvesting is not the result of a decrease in demand or from lack of trying. It is a clear indication that oysters are overfished, a situation compounded by dramatic losses to disease and habitat degradation. But numbers are once again rising, thanks to North Carolina’s Division of Marine Fisheries, North Carolina Coastal Federation, the North Carolina Aquariums and a host of other organizations. Working together, they are making great strides in the protection of natural reefs and the restoration of lost beds. Although most of us think of oysters only at oyster roasts, their importance reaches much further than satiation of our hunger. Oysters and their reefs filter waters, and they create habitats for gamefish, crabs and – most important – for other oysters. Each oyster filters up to 50 gallons of water in a day. Without oysters, far more algae, bacteria and other substances could deplete oxygen and contaminate (or otherwise render uninhabitable) our marshes and estuaries – important nursery grounds for commercial shrimp, fish and blue crabs. The economic impact of such damage could prove disastrous in coastal regions. The best place for a new oyster to grow is on an old oyster. Old oysters provide strong footing for newcomers, and their shells accumulate to build reefs. Oysters cement themselves to each other and grow into clusters, which form protective habitats for numerous organisms, such as polychaete worms and soft-shelled blue crabs. Oysters provide food for many predators, such as sea stars, drum and oystercatchers. Oyster reefs serve as a substrate stabilizer, allowing clams and aquatic plants a chance to thrive, and give small fish like gobies and blennies a place to spawn. Barnacles and anemones benefit from the sturdy roost that oyster clusters provide. How can old oysters provide substrate for new oysters if the oysters are collected and eaten? It’s simple: We recycle their shells. Collective agencies are teaming up to create oyster shell recycling bins in coastal areas and publicize their locations. As further encouragement, the North Carolina legislature has mandated that oyster shells not be allowed in landfills. Now, instead of tossing shells in our driveways or flowerbeds, we can gather them after a roast and take them to the nearest bin. After six months, the shells are cleaned, bagged and distributed to potential oyster reef sites. Each site is seeded with oyster larvae and marked as a no-harvest area until the habitat has been established. Many local restaurants are also pitching in. Before ordering those delectable morsels, ask your waiter if they recycle. If not, ask for a “shell bag” and recycle them yourself, or consider another appetizer. To find the closest recycling bin in your area, log on to www.ncfisheries.net. The North Carolina Aquariums have been designated to head an oyster hatchery development team. Incorporating multiple federal, state, and public agencies, the team will research, and eventually build and maintain, an oyster hatchery to supply oyster larvae for reef establishment. Educational activities will embrace oyster education, shell recycling, oyster habitat research and hatchery education, and will help distribute information to public and commercial sectors. For more information, stay in touch online at www.ncaquariums.com. We’ll post periodic updates on the hatchery teams’ feasibility study, education efforts, and links to additional oyster sites. Background photo courtesy Peggy Sloan Page 10 Semipalmated plover feeds upon the mud flats and oyster reefs. (Peggy Sloan)
Object Description
Description
Title | Conserving the Cape Fear : a semiannual publication of the North Carolina Aquarium at Fort Fisher |
Other Title | Semiannual publication of the North Carolina Aquarium at Fort Fisher |
Date | 2005 |
Description | Volume 3, Issue 1 (Winter 2005) |
Digital Characteristics-A | 5425 KB; 10 p. |
Digital Format | application/pdf |
Pres File Name-M | pubs_serial_conservingcapefear2005winter.pdf |
Full Text |
Photo courtesy Mike Suchy
ConCservianag ptphe e FeVaoal. III Irsrsue 1 Winter 2005
A semiannual publication of the
North Carolina Aquarium at Fort Fisher
Conserving the
Inside this issue...
Managing a Fishery: A
Complicated Answer to a
Simple Question. P. 2
Turtle Trails: Where Do Our
Turtles Go? P. 4
The Butterflies of Ft. Fisher P. 6
Why Do Marine Mammals
Strand? P. 8
Conservation Through
Appreciation...A Different
Approach P. 9
Why Recycle Oyster Shells? P.10
Fisheries
Management
“A
complex
answer to
a simple
question.”
By Fritz Rohde
Fisheries Biologist
NC Division of Marine Fisheries
Continued page 3
Catch of the Day: Grouper, porgy and snapper, respectively ( Fritz Rohde) Page 2
What does it take to manage a
fishery? This may seem like a simple
question, but it is one that requires a
complex answer. In the “old” days, it may
have been by the seat of your pants or by
the “Bell System,” wherein whoever called
the most often got the management
decisions they wanted. But since the early
1980s for fisheries in the Atlantic Ocean,
and since 1997 for our state fisheries,
documents called Fishery Management
Plans (FMPs for short) are prepared to
ensure the long-term viability of these
fisheries.
These FMPs are developed, with
public input, to describe the nature and
problems of a fishery and to propose
management regulations to conserve the
fishery. The goal of an FMP is to prevent
overfishing while allowing optimum yield.
Overfishing can be defined as harvesting at
a rate greater than what will meet the
management goal (i.e., sustain the species)
while optimum yield can be summed up as
the harvest level for a species that achieves
the greatest overall benefits, including
economic, social, and biological
considerations.
So, what is needed for an FMP?
An FMP contains a great deal of
information on the biology of the fish
stock (a harvested or managed unit of fish
may be a single species or a multi-species
complex) and the fishery (recreational and
commercial landings, gear, areas fished,
and socio-economic data). The Plan
identifies the problems in a fishery and
proposes management measures (fishing
regulations) to correct the problems. One
of the key components of a FMP is the
stock assessment that describes the
conditions or status of the stock. This
incorporates as much as possible about
the biology of the species in the stock and
about the fishery on this stock. The
biological information can include the
age at which it first spawns, the ages of
the fish in the population, how many eggs
are produced, and the ratio of females to
males. Information on the fishery may
include types of gear used, the
commercial and recreational landings
over a large number of years, the age
structure of the fish that are harvested, the
fishing effort expended, and the ratio of
females to males. Since the goals of an
FMP are to prevent overfishing and to
rebuild overfished stocks, how are we
doing? The first state FMP was approved
in 1998 (blue crab). Since then, nine
others have been completed (two are still
in draft form).
“Whether the fishermen or the
modelers (scientists) are right is
difficult to ascertain. Undoubtedly,
the answer lies somewhere in
between.”
Page 3
Snapper, iced down prior to market. (Fritz Rohde)
Commercial fishing is a major industry on our coast. (Fritz Rohde)
Given the relatively short period of
time involved, it is too soon to tell for most
of them but there have been some
encouraging signs with the red drum stock
and striped bass in Albemarle Sound. On
the federal level, the Snapper-Grouper FMP
has been around since 1983. It is such a
complex fishery (with 73 species being
managed in it) that currently the South
Atlantic Management Council is
undergoing the 13th amendment to the Plan.
Previous amendments have established size
limits, bag limits and spawning season
closures, and have limited or prohibited
certain types of fishing gear and reduced
the number of commercial fishermen. One
idea that has been discussed by the Council
for a number of years is Marine Protected
Areas where fishing for these species
would be off limits. There is disagreement
as to how successful the current
management measures have been.
Many fishermen believe that the
regulations have had a positive impact on
the fish stocks and they are catching fish at
the same rates and sizes as they did years
ago. On the other side of the coin are
results of computer modeling done by the
National Marine Fisheries Service
indicating that many of these species are
still overfished and that the current
regulations will not allow the stocks to
recover.
Managing a fishery does not have
the preciseness present in the other
sciences. Whether the fishermen or the
modelers are right is difficult to ascertain.
Undoubtedly, the answer lies somewhere in
between.
A complex answer to a simple
question.
For specific fisheries stock status
and other information log on to
www.ncfisheries.net
Imagine walking along the
beach and spotting a live sea
turtle, weighing more than 100
pounds, stranded in the surf. Each
year North Carolina's Sea Turtle
Volunteers are called on to carry
sick or injured sea turtles to one of
two rehabilitation facilities in the
state. Dedicated volunteers staff
both the NEST Rehabilitation
Facility at the North Carolina
Aquarium on Roanoke Island and
the Topsail Sea Turtle Hospital
located in Topsail Beach. The
goal of both programs is to release
healthy sea turtles back into the
wild.
Rehabilitating sea turtles
requires long hours, and
appropriate husbandry and
veterinary care. But watching
greens, loggerheads and Kemp's
ridleys crawl back into the ocean
after spending months in tanks is
an incredible reward. For years
we wondered whether these
animals survived, and where they
traveled after release. A study
designed to answer these
questions, and funded by the
Institute of Museum and Library
months when water temperature
dropped. A second group migrated
farther south, along the coasts of
South Carolina, Georgia, and as far
as Florida. The third group moved
offshore into the mid north Atlantic,
and over wintered in the warmer
waters of the Gulf Stream current.
Once coastal water temperature
warmed, loggerheads returned north
of Cape Hatteras. Some entered the
sounds behind the barrier islands,
while others continued migrating
offshore, one as far north as
Maryland.
We have yet to determine why
a particular sea turtle chooses one
pattern over another. Water
temperature does appear to be a
critical factor in loggerhead
migration, with most preferring to
remain in waters above 10 C (50 F).
Sea turtles can become stranded for
many reasons, some of which are
human caused. For example, some
sea turtles will ingest plastic bags or
other pieces of trash thinking they
might be food. Contaminants in the
water may also sicken sea turtles.
“Bogue” surfacing to breathe after having the transmitter attached (Joanne Harcke)
Services, has yielded some
incredible results.
Since September 2003, ten
loggerhead sea turtles (Caretta
caretta) were released from the
NEST Rehabilitation Facility at the
Aquarium on Roanoke Island and
four loggerheads were released from
the Topsail Sea Turtle Hospital, all
with satellite transmitters attached to
the carapace (upper shell).
Biologists from Wildlife
Resources Commission used a two-part
epoxy resin to securely fasten
the transmitters. Each transmitter
was programmed to send location
coordinates and water temperature
data to satellites, which then beamed
the information to a receiving station
on the ground.
Using data collected from a
Duke University study on wild-caught
loggerheads, we were able to
compare the post-release movements
of our rehabilitated sea turtles.
Regardless of whether they were
wild-caught or rehabilitated, three
patterns emerged. One group of
loggerheads remained in the coastal
waters of North Carolina, migrating
south of Cape Hatteras in the winter
Where in
the World
Do Our
Sea
Turtles
Go?
TURTLE
TRAI
By Joanne Harcke LS
Conservation and Research Coordinator
North Carolina Aquarium at Ft. Fisher
Continued page 5 Page 4
All species of sea turtle must
surface to breathe, which makes
them vulnerable to boat strikes.
With proper care, we now know,
these animals can be successfully
rehabilitated and released back to
the wild.
But rehabilitation takes time
and money; therefore preventing sea
turtle strandings is a critical
component of saving these
endangered and threatened species.
Picking up trash, watching from a
safe distance, always disposing of
used fishing equipment properly,
and improving water quality are
actions each of us can take to help
preserve and protect sea turtles.
So, the next time you're
walking along the beach looking out
across the ocean, consider the
amazing journey of the loggerhead.
And while we have learned the
Transmitter attached, “Obie's” released at Topsail Beach (Jacob Rudolph)
answers to some questions,
many others are waiting to be
discovered.
http://www.ncaquariums.com/turtletrails/
For more information on the
Turtle Trails Project, log on to:
Page 5
A visit to the North Carolina Aquarium
at Fort Fisher just wouldn't be complete
without a stroll through the Memorial
Garden. There are native trees and
shrubs, salt-tolerant landscape plants,
colorful flowerbeds, a birding deck and
beautiful memorial sculptures. There are
also butterflies - lots of butterflies!
Late summer and early autumn
are the perfect time for butterfly
watching. Spring caterpillars have
become adults and migrants move
through the area, coming from both north
and south. The highest diversity of
species occurs in September.
We began preparing our gardens
for butterflies one year ago, by seeding
copious amounts of curly parsley, dill and
fennel all host plants for several species
of butterflies, most notably the
swallowtails (we have six species that
occur along the coast here). We also
grew garden varieties of cabbage, carrots,
broccoli, and alfalfa (from sprouts sold in
supermarkets!). All these easy-to-grow
plants attract adult butterflies for the
purpose of egg laying. Perhaps the best-known
example of a butterfly host plant
is the milkweed. These moisture-loving
perennials (there are several species) are
the sole host plants for monarch (Danaus
plexippus) and queen (D. gilippus)
butterflies. We seeded milkweed in mid-summer
and had monarchs fluttering
around the young plants before we got
them planted!
Of course, all of our native
butterflies are adapted to native plant
species of the region. It ought to be taken
into consideration that as land is cleared
for development and non-native
landscape plants replace natives, many
species of butterflies (and other animals)
lose what is necessary for their
reproduction. Some examples may be
found in some of our largest and showiest
butterflies. The host plants of the
spicebush swallowtail (Papilio troilus)
include spicebush, a wetland plant, and
sassafras, a common shrub in upland
woods and edges, which are routinely
clear-cut. Another upland shrub, the
paw-paw, is host plant to the stunning
zebra swallowtail (Eurytides marcellus).
And a true southern beauty, the
palamedes swallowtail (Pterourus
palamedes), is a creature of the
wetlands. The larvae feed on red bay,
sweet bay and, again, sassafras. There
The Butterflies
Of
Fort Fisher
By Melanie Doyle
Horticulturist
North Carolina Aquarium at Fort Fisher
are almost 190 species of butterflies
occurring in North Carolina, and
many of those are found only along
the coast, some just in our
southeastern region. A few species
seen here in the fall actually have
migrated north to feed. Many of the
beautiful pale yellow sulphur species
(where the term “butter” fly may have
come from) move north in late
summer, creating eye-catching
“flocks” of flittering yellow above
open fields and gardens. The large
cloudless sulphur (Phoebis sennae)
comes our way from the tropics, South
America, the Caribbean, and southern
Florida. It isn't understood why these
animals come so far north in the fall
(as far as New York!), and why they
Page 6
Longtail skipper (Dick Roberts)
Monarch butterfly (Dick Roberts)
Continued page 7
perish with the onset of winter, not returning
south again. But while here, they feed on the
nectar of almost any flower they find (here at the
Aquarium they love our tropical hibiscus and
lantana).
So far this summer (since mid-August),
we have identified, with confidence, thirteen
species of butterflies on the Aquarium grounds.
Many, however, are small and elusive and will
require capturing in order to identify to the
species level. The skippers, hair-streaks and
satyrs are only about one inch long, and primarily
brown-- much more difficult to identify than the
larger, colorful species. While we will continue
watching, identifying and enjoying our butterflies
over the next few weeks, preparations are already
underway for next year. We continue to add both
host and nectar plants to the gardens, as well as a
feeding station in order to attract those species
(such as the red admiral) that do not feed on
nectar, but instead on sap, carrion and rotting
fruit. Also, the limitation of insecticides is very
important as any broad-spectrum chemical
sprayed for insect control readily affects
butterflies.
Remember, in addition to being beautiful
residents and visitors in our gardens, butterflies
are a good indicator of the overall health of our
surrounding environments!
Plants for adult butterflies to lay eggs
To attract migrating butterflies
Hibiscus
Lantana
Pentas
Gilardia
Echinacea
Curly parsley (lots)
Garden varieties of:
cabbage, carrots, broccoli, and alfalfa
Milkweed
Spicebush
Sassafras
Paw-paw
Sweet bay
Red bay
Sassafras
Not all la ts listed p n
a e native. se r U
nat e plant w en iv s h
ossible p .
Cut out the list when you’re ready to shop.
Page 7
Monarch butterfly (Dick Roberts)
Since Aristotle’s time, around 350
B.C., people have been attempting to
discover why marine mammals “strand.”
A stranding is defined as the beaching,
either alive or dead, of a marine mammal.
Marine mammals include whales, dolphins,
seals, sea lions, walruses, sea otters, polar
bears and others.
Focused scientific studies on
strandings really began in the 1970s
(Malakoff 2001). Some stranding of
marine mammals can be controversial, and
there is often no clear evidence as to why
these animals come ashore.
Most often, marine mammals
strand as single individuals (National
Marine Life Center). Occasionally mass
strandings, defined as three or more
individuals, occur. In some cases up to 400
individuals have stranded on the beach at
one time. In the United States, about 3,000
to 4,000 marine mammals strand per year.
About 75 percent of the time, these animals
are already dead when they wash ashore
(Malakoff 2001).
Strandings can have many
potential causes or contributing factors,
some natural and some human-related. For
single strandings, these include:
1. health complications associated with
pregnancy
2. separation of a dependent calf from its
mother
3. predation by sharks or killer whales,
4. natural biotoxins (e.g., red tide
poisoning)
5. disease, parasitism, and old age
ingestion of trash
6. entanglement in fishing gear
7. vessel strikes (Malakoff 2001, National
Marine Fisheries Service, National
Marine Life Center).
For mass strandings, hypotheses for
causes include:
1. social cohesion, (If an individual in the
group becomes ill and strands, the rest of
the pod will follow)
2. geomagnetic disturbances that may
cause navigational errors,
3. pursuit of prey too close to shore,
4. barriers to, or disturbances in,
echolocation in shallow water
5. Complex geographic oceanic
conditions such as abnormally high or
low tides (Malakoff 2001, National
Marine Fisheries Service, National
Marine Life Center).
Live marine mammal strandings
represent the most difficult event faced
by stranding-response personnel. The
decision to euthanize or
release/rehabilitate is always done in
consultation with a veterinarian. Most
often, the decision for a single stranded
individual is to euthanize, based upon the
animal’s health condition. Malakoff
(2001) stated, “There must be both a
humane society dealing with the welfare
of stranded animals and an objective
institution collecting scientific data.”
Guidelines have been set up as to when it
is proper to euthanize an animal or when
to release it back into the wild.
“Euthanasia shall only be performed by
an attending veterinarian or by a person
acting under the direct supervision of an
attending veterinarian” (Marine Mammal
Stranding Agreement 2004). Scientists
and veterinarians try to learn as much as
possible from each stranding. Tissue
samples collected from dead stranded
animals can not only help determine the
cause of death, but also aid in
discoveries about anatomy, ecology, and
evolution. The life histories of some
marine mammals are known exclusively
through stranding data. They also tell us
information about their diets, how many
young they have, and how old they are
when they first reproduce (Malakoff
2001, National Marine Fisheries
Service).
Why
Marine
Mammals
Strand
By Justin Perrault
Marine Science Student
University of North Carolina at Wilmington
Works Cited:
Malakoff, D. Marine Mammals: Why do Marine Mammals Strand?
Science 2001 293: 1755.
Marine Mammal Stranding Agreement Between National Marine
Fisheries Service of the
National Oceanic and Atmospheric Administration Department of
Commerce and [Stranding Network Organization]. Article I.
General Authority. 2004. [Available from the Internet.]
URL: |
OCLC number | 807975622 |