TWIN D'S
02-09-2004, 09:43 AM
It says the fish go north in the winter?
**************
Scientists keep track of area?s striped bass
By JARRETT RENSHAW Staff Writer, (609) 978-2015
LITTLE EGG HARBOR TOWNSHIP - Have you ever wondered about the intimate details of a striped bass's social life?
Its comings and goings, who it's spending time with and why?
Maybe you didn't, but a half-dozen Rutgers Univer-sity scientists do.
Scientists from the Rutgers University Marine Field Station have been working for nearly two years trying to decode the seemingly random migration patterns of the striped bass.
Take Blues Clues, one of the test stripers, for example. The striper likes to spend its summers in the Great Bay, just outside the Mullica River, and, then, like a lot of natives, flees the coop for a more favorable environment - a pattern he has followed twice on similar time schedules.
"It appears the fish may have found a habitat, but it will be interesting to see if he comes back in May again," said Tom Grothues, one of the project's lead scientists.
There is another striper from Maine, who made the trip to Great Bay from the New England state in two months, showing that stripers can travel long distances in a short amount of time.
The project is one of two in the nation - the other being in Maine - that tracks striped bass movements using high-tech equipment.
The 2-year-old project includes 46 striped bass that are being tracked in the Mullica River/Great Bay estuary system with lipstick-sized tagging devices that have been inserted in their bellies.
The trackers emit a signal that is picked up by high-tech underwater microphones that help record the movements of the fish.
The tags carry a two-year battery and a transmitter that emits a ping that creates an identification code. The sound's frequency - which can be disrupted by boat radios - is so high that humans cannot hear it. The signal is powerful enough to travel a half mile through water.
Some of the most important microphones are placed in the channels of the Great Bay and track the fish as they enter and exit the estuary system.
The movements are then plotted on graphs, put into databases and twisted and turned in an attempt to make sense of their movements. It is comparable to making sense out of thousands of dots and lines on a map.
"Even though we have been studying the movements for some time now, we are still holding back on announcing any serious results as of yet," Grothues said.
The old way of tagging fish -with a simple external tag that doesn't allow for electronic monitoring - made it impossible to learn where the populations went through the year. The technology in the Rutgers project allows scientists to know when striped bass leave, how often they leave, where they go and when they return.
The public can "buy" a striper for a $267 donation, which allows them to name the fish. Then, like everybody else, they can track the fish on the Web at
www.stripertracker.org (http://www.stripertracker.org)
to find out if the fish is hanging out by a buoy or near the Mullica River.
The 46-tagged stripers are no longer in the estuary system. This may come to a surprise to some local fisherman, Grothues said, because the prevailing notion is striped bass don't move out of the system.
"It is true that many stripers don't move out of the system, but those are the smaller ones and we only tag the larger fish," he said.
The scientists are looking forward to the spring, when they can be expected to return from northern waters.
They will then be able to draw conclusions about the habitat of the Great Bay system based on the amount of returns.
Station biologists and technicians go on fish-finding expeditions -with the vital help of local fishermen - and when they catch the fish, the tags are implanted in the stomach through an inch-long slit after the fish has become anesthetized.
After the 10-minute process, the fish are awakened and are placed back in the water.
Migration is the movement of animals in large numbers from place to place. Many different types of animals migrate, and depending on the animal, the trip may be as long as an entire lifetime or as short as a few months.
Some animals follow a specific route during the course of a migration, while others may follow a less direct path.
One of the major goals of the Rutgers project is to put areas of habitat into understandable terms, which could redefine how conservationists and politicians approach precious habitat areas.
Habitat areas are ones that are believed to be essential to a species by providing shelter and food.
Grothues said he wants to know more than just how striped bass move; he wants to understand why they move.
The scientists will analyze the amount of time a fish spends in certain areas. This is expected to lead to discoveries about what the environment provides for the fish.
"We don't know exactly what the fish is doing at times in certain areas, but we can put a number on the amount of time a fish spends in an area," Grothues said
Equipped with the fish's motives for selecting certain habitats, Grothues said conservationists and politicians might make more informed decisions about preserving areas in the future.
They hope to expand the project to other coastal regions of New Jersey, which they feel will give them a more comprehensive view of the population.
To e-mail Jarrett Renshaw at The Press:
JRenshaw@pressofac.com
**************
Scientists keep track of area?s striped bass
By JARRETT RENSHAW Staff Writer, (609) 978-2015
LITTLE EGG HARBOR TOWNSHIP - Have you ever wondered about the intimate details of a striped bass's social life?
Its comings and goings, who it's spending time with and why?
Maybe you didn't, but a half-dozen Rutgers Univer-sity scientists do.
Scientists from the Rutgers University Marine Field Station have been working for nearly two years trying to decode the seemingly random migration patterns of the striped bass.
Take Blues Clues, one of the test stripers, for example. The striper likes to spend its summers in the Great Bay, just outside the Mullica River, and, then, like a lot of natives, flees the coop for a more favorable environment - a pattern he has followed twice on similar time schedules.
"It appears the fish may have found a habitat, but it will be interesting to see if he comes back in May again," said Tom Grothues, one of the project's lead scientists.
There is another striper from Maine, who made the trip to Great Bay from the New England state in two months, showing that stripers can travel long distances in a short amount of time.
The project is one of two in the nation - the other being in Maine - that tracks striped bass movements using high-tech equipment.
The 2-year-old project includes 46 striped bass that are being tracked in the Mullica River/Great Bay estuary system with lipstick-sized tagging devices that have been inserted in their bellies.
The trackers emit a signal that is picked up by high-tech underwater microphones that help record the movements of the fish.
The tags carry a two-year battery and a transmitter that emits a ping that creates an identification code. The sound's frequency - which can be disrupted by boat radios - is so high that humans cannot hear it. The signal is powerful enough to travel a half mile through water.
Some of the most important microphones are placed in the channels of the Great Bay and track the fish as they enter and exit the estuary system.
The movements are then plotted on graphs, put into databases and twisted and turned in an attempt to make sense of their movements. It is comparable to making sense out of thousands of dots and lines on a map.
"Even though we have been studying the movements for some time now, we are still holding back on announcing any serious results as of yet," Grothues said.
The old way of tagging fish -with a simple external tag that doesn't allow for electronic monitoring - made it impossible to learn where the populations went through the year. The technology in the Rutgers project allows scientists to know when striped bass leave, how often they leave, where they go and when they return.
The public can "buy" a striper for a $267 donation, which allows them to name the fish. Then, like everybody else, they can track the fish on the Web at
www.stripertracker.org (http://www.stripertracker.org)
to find out if the fish is hanging out by a buoy or near the Mullica River.
The 46-tagged stripers are no longer in the estuary system. This may come to a surprise to some local fisherman, Grothues said, because the prevailing notion is striped bass don't move out of the system.
"It is true that many stripers don't move out of the system, but those are the smaller ones and we only tag the larger fish," he said.
The scientists are looking forward to the spring, when they can be expected to return from northern waters.
They will then be able to draw conclusions about the habitat of the Great Bay system based on the amount of returns.
Station biologists and technicians go on fish-finding expeditions -with the vital help of local fishermen - and when they catch the fish, the tags are implanted in the stomach through an inch-long slit after the fish has become anesthetized.
After the 10-minute process, the fish are awakened and are placed back in the water.
Migration is the movement of animals in large numbers from place to place. Many different types of animals migrate, and depending on the animal, the trip may be as long as an entire lifetime or as short as a few months.
Some animals follow a specific route during the course of a migration, while others may follow a less direct path.
One of the major goals of the Rutgers project is to put areas of habitat into understandable terms, which could redefine how conservationists and politicians approach precious habitat areas.
Habitat areas are ones that are believed to be essential to a species by providing shelter and food.
Grothues said he wants to know more than just how striped bass move; he wants to understand why they move.
The scientists will analyze the amount of time a fish spends in certain areas. This is expected to lead to discoveries about what the environment provides for the fish.
"We don't know exactly what the fish is doing at times in certain areas, but we can put a number on the amount of time a fish spends in an area," Grothues said
Equipped with the fish's motives for selecting certain habitats, Grothues said conservationists and politicians might make more informed decisions about preserving areas in the future.
They hope to expand the project to other coastal regions of New Jersey, which they feel will give them a more comprehensive view of the population.
To e-mail Jarrett Renshaw at The Press:
JRenshaw@pressofac.com