GBUSA
09-30-2004, 12:54 PM
I posted an inquire as to the killing of tournament fish in Erie and the biological question of what was then and is now. I got many posts with opinions, but I wanted the facts. Since then, I have contacted the best of the best NOAA, OHDNR and the top biologists in the field. Please let us accept the facts over opinions. I had many conversations that address the impact of eyes/perch and the trout-plus the influx of exotics on a daily basis. Here it is and feel free to write if you need more. Someone, keep this in their archives for future debates next spring PWT and more.
GB&GBUSA,
Jerry
Below are responses to your Lake Erie questions. Please let me know if you need anything clarified or if you have any further questions.
Also, I would appreciate it if you could give me a link to any message boards that you post the responses on. I'm always interested in anglers' responses to our information and I would be interested in following the boards that you post on.
Take care,
Travis
Travis Hartman
Fisheries Biologist
Ohio Department of Natural Resources
Division of Wildlife
Sandusky Fish Research Unit
305 E. Shoreline Dr.
Sandusky, Ohio 44870
Phone: 419-625-8062
Fax: 419-625-6272
Travis.Hartman@dnr.state.oh.us
Question:
1. When a tournament or fisherman of L. Erie and inland bodies of water catch walleyes, put them in their live-well, run around the lake, can they survive a release and what % if any? What research do you have to make your point? Can I get a copy of it?
Iowa, Wisconsin, Minnesota and Ohio have all studied walleye tournament mortality at the time of weigh-ins and also delayed mortality after release.
The following is a summary of various studies as reported in the American Fisheries Society/North Central Division Walleye Technical Committee 2000 summer workshop notes:
Iowa, Mississippi River- Weigh-in mortality varied from less than 1% to 24%. 5 day delayed mortality ranged from 37% to 78% (55.8% average). Important factors affecting survival included livewell oxygen concentration and water temperatures.
Iowa, Lake Rathbun- Mortality at the time of weigh-in was 3%, but delayed mortality after 4 days was 76%.
Wisconsin, Winnebago system- Delayed mortality after 48 hours was 22% for fish that were not fizzed, 76% for fizzed fish, and 4% for a control group of fish that was caught by electroshocking and was not fizzed.
Ohio, Lake Erie- The PWT tournaments attempted live-release tournaments in '91, '92 and '93. 1991 was held during a calm period. 1,597 walleye were fizzed with 1% mortality at 20 hours. Mortality at 6 months after the tournament was estimated at an additional 3%. The 1992 PWT was held during 3 to 6 feet waves. Mortality for non-fizzed fish was 100% after 9 days, compared to 53% mortality for fizzed fish. Fish that died in 1992 were found to have spine-induced abdominal cavity puncture wounds from being held in livewells in rough seas. During the 1993 PWT over 2,000 fish were fizzed resulting in low immediate mortality, but delayed mortality was found to be high in the following days.
Minnesota published a Mille Lacs Lake walleye tournament study in the North American Journal of Fisheries Management (Goeman, T. J. 1991. Walleye mortality during a live-release tournament on Mille Lacs, Minnesota. North American Journal of Fisheries Management 11: 57-61). The Mille Lacs Lake results were as follows:
Mortality at the time of weigh-in 1.0 to 6.2%.
Delayed mortality after 5 days ranged from 5.7% to 47.1%.
Total tournament mortality, including all tournament days (both weigh-in and delayed mortality), was estimated at 40%.
The three factors that appeared to have the most impact on survival were weigh-in stress, weather conditions and density of fish in the boats' livewells. Of the fish that died the sex ratio was nearly 50:50 and there was not a relationship between fish size and probability of survival.
Summary of tournament research results:
It's clear from all of the tournaments studied that delayed mortality is higher than mortality observed at weigh-ins. The severity of delayed mortality seems to be strongly linked to wave conditions and surface temperature during the tournament. Larger waves and higher temperatures reduce the likelihood of survival of released fish. It is not clear if fizzing improves the survival rate of released fish.
2. With the complex eco system of Erie (zebras, gobies, steelies the eating machine, perch AND MANY MORE THAT CAN COME DAYLY) and the boom of perch, why have the walleye gone down-hill since 1970 when it is stated that stocking is more important than the spring hatch? Does the lake simply get less fry than 30 years ago? wHY THEN AND NOT NOW?
Based on walleye population estimates (adult fish, age-2 and older) by the Walleye Task Group of the Great Lakes Fishery Commission's Lake Erie Committee the population was at its largest in 1988 at around 70 million fish. Since 1997 the population has fluctuated between 16 and 29 million fish. The current population estimate for 2004 is just over 19 million. The Lake Erie walleye population is almost solely supported by natural reproduction, most of which takes place on the Ohio reef complex (Camp Perry firing range) and in the Maumee, Sandusky and Grand Rivers. Minimal stocking occurs in Pennsylvania and New York, but those stocked fish realistically don't make a population-level contribution. The stockings might influence localized areas, but stocking alone would never support walleye sportfishing on Lake Erie.
The Lake Erie walleye fishery is very year class dependant. Multiple strong year classes within a few years of each other lead to good fishing. The trend since the mid '90's has been an occasional average year class surrounded by poor to non-existent year classes. Right now the fishery is dominated by the '99 and 2001 year classes with larger fish coming from the '96, '94, '93, '91 and '90 year classes. Female walleye larger than 27" and male walleye larger than 24" are usually 10 years old or older. We are finding that walleye can live in excess of 20 years, with fish from the exceptional 1982 year class still occasionally being caught.
While the size and survival rate of each year's hatch is mostly determined by weather conditions the management of allowable harvest of the resulting year classes is up to management agencies around the lake. Reduced Total Allowable Catches (the number of walleye that are allowed to be harvested each year by each management agency, i.e. ODNR, PA FBC, MDNR, OMNR, NYDEC) have been agreed upon by all agencies to help conserve the walleye population during this period of lower population numbers. The enormous year class from 2003 will help to fuel the population in coming years.
3. How many fry are stocked today compared to 1970? And, is PA matching the fry amount?
Currently there is very limited walleye stocking in Lake Erie. A Pennsylvania walleye club stocks approximately 800,000 very early stage larvae into Presque Isle Bay each spring. The survival of the stocked fish and their contribution to the population has not been documented. New York is currently attempting to rehabilitate walleye in the Buffalo River by stocking 2" fingerlings in the river for the next 5 to 7 years. This was the first year and 26,000 fingerlings were stocked. The stockings will not continue past the 5 to 7 year time period. The stockings will be evaluated to find out whether or not a reproducing population can be re-established in the Buffalo River.
During the years that the Put-In-Bay hatchery was in operation ODNR did stock walleye in Lake Erie. There was not any proof that the stocked walleye actually contributed to the population. Lake Erie has plenty of spawning habitat between the reefs and the rivers. In years that the conditions are right the native walleye produce incredible hatches. In the years that we have year class failures the survival of the hatch is reduced by weather conditions. In those poor weather years that did not support the hatch stocked fish would also likely face high mortality. There will not be any large scale stocking of walleye in Lake Erie any time soon.
Wildinfo.Fish@dnr.state.oh.us
Jerry,
Water depth aside, I am not aware of any published research on the effects
of angler catch and release on subsequent survival of walleye in Lake Erie.
Published studies on hooking mortality, or post-release mortality, for a
variety of fish species indicate that water temperature tends to be a major
factor (warmer the water, higher the mortality for all fishes). Other
factors, like water depth, hook type, handling time, weather conditions,
species of fish, and fishing technique are also important. Keep in mind
that this kind of research is difficult to do without introducing
experimental error, especially in large lakes, where released fish are often
retained in some kind of enclosure for evaluation, that in itself can
stress
fis!
h.
With respect to your specific questions:
1.) From our monitoring experience with walleye tournaments in Ohio waters
of Lake Erie, we believe that most walleyes retained in live wells for
several hours under normal lake conditions will not survive when released.
Therefore, we do not recommend catch-release for walleye tournaments on Lake
Erie. We believe that most walleye caught
and immediately released will
survive unless foul-hooked or mishandled. Healthy fish retained in
properly-maintained live wells under relatively calm lake conditions for
short time periods probably have a strong chance of surviving. In short,
Ohio law stipulates that any fish released must be alive and in good
condition. The decision to keep the fish is best made at time of capture.
2.) The Lake Erie walleye population is not maintained by stocking
programs
and never has been. Walleye abundance fluctuates with annual levels of
natural reproduction, as influenced by a number of environmental factors
(temperature, wind, oxygen, food supply, predators/competitors)in ways that
are quite complex and difficult to understand and predict. Adult walleye
abundance is lower now than it was in the peak period of the mid to late
1980s because the reproductive pattern is different than it was back then,
when we measured above-average hatches in 4 of 5 years between 1982 and
1986. Walleye must survive at least two years in the lake to contribute to
fisheries, involving several life stages from eggs to fry to fingerlings to
older fish. It is much more complicated than simply "numbers of fry". The
addition of exotic species to the Lake Erie ecosystem has further
complicated our understanding of walleye reproduction.
3.) Ohio has not
stocked walleyes in Lake Erie since 1971. There is no
interagency initiative to stock walleyes or to "match" what any agency does
in their jurisdiction for whatever purpose. Collectively, agencies are
dependent on natural reproduction to sustain fisheries lakewide.
-----Original Message-----
From: gbusa911@hotmail.com [mailto:gbusa911@hotmail.com]
Sent: Monday, August 02, 2004 10:31 AM
To:
Wildinfo
Subject: Comments from users
Gerald Roman at gbusa911@hotmail.com
I need your best biologist/researcher for the Erie Walleye to set the
record
straight on the killing/releas of walleyes from deep water. PREFERABLY, I
WILL NEED FACTUAL, DOCUMENTED RESEARCH. This will be worth your time as it
is a topic of controversy for years that needs to be addressed on all major
boards.
Question:
1. When a tournament or fisherman of L. Erie and inland bodies of water
catch walleyes, put them in their live-well, run around the
lake, can they
survive a release and what % if any? What research do you have to make your
point? Can I get a copy of it?
2. With the complex eco system of Erie(zebras, gobies, steelies the eating
machine, perch) and the boom of perch, why have the walleye gone down-hill
since 1970 when it is stated that stocking is more important than the spring
hatch? Does the
lake simply get less fry than 30 years ago?
3. How many fry are stocked today compared to 1970? And, is PA matching the
fry amount?
GB&GBUSA,
Jerry
412 486 6133
Hello Jerry,
Water depth aside, I am not aware of any published research on the effects
of angler catch and release on subsequent survival of walleye in Lake Erie.
Published studies on hooking mortality, or post-release mortality, for a
variety of fish species indicate that water temperature tends to be a major
factor (warmer the water, higher the mortality for all fishes). Other
factors, like water depth, hook type, handling time, weather conditions,
species of fish, and fishing
technique are also important. Keep in mind
that this kind of research is difficult to do without introducing
experimental error, especially in large lakes, where released fish are often
retained in some kind of enclosure for evaluation, that in itself can stress
fish.
With respect to your specific questions:
1.) From our monitoring experience with walleye tournaments in
Ohio waters
of Lake Erie, we believe that most walleyes retained in live wells for
several hours under normal lake conditions will not survive when released.
Therefore, we do not recommend catch-release for walleye tournaments on Lake
Erie. We believe that!
most wa
lleye caught and immediately released will
survive unless foul-hooked or mishandled. Healthy fish retained in
properly-maintained live wells under relatively calm lake conditions for
short time periods probably have a strong chance of surviving. In short,
Ohio law stipulates that any fish released must be alive and in good
condition. The decision to keep the fish is best made at time of capture.
2.) The Lake Erie walleye population is not maintained by
stocking programs
and never has been. Walleye abundance fluctuates with annual levels of
natural reproduction, as influenced by a number of environmental factors
(temperature, wind, oxygen, food supply, predators/competitors)in ways that
are quite complex and difficult to understand and predict. Adult walleye
abundance is lower now than it was in the peak period of the mid to late
1980s because the reproductive pattern is different than it was back then,
when we measured above-average hatches in 4 of 5!
years b
etween 1982 and
1986. Walleye must survive at least two years in the lake to contribute to
fisheries, involving several life stages from eggs to fry to fingerlings to
older fish. It is much more complicated than simply "numbers of fry". The
addition of exotic species to the Lake Erie ecosystem has further
complicated our understanding of walleye reproduction.
3.) Ohio has not stocked walleyes in Lake Erie since 1971. There is
no
interagency initiative to stock walleyes or to "match" what any agency does
in their jurisdiction for whatever purpose. Collectively, agencies are
dependent on natural reproduction to sustain fisheries lakewide.
Thanks for your interest in Lake Erie walleye and feel free to contact me if
you have other questions.
Roger L. KnightLake Erie Fisheries Program AdministratorODNR Division of WildlifeSandusky Fisheries Research Station305 E. Shoreline DriveSandusky OH 44870(419) 625-8062(419) 625-6272 faxroger.knight@dnr.state.oh.us
Hageman <hageman.2@osu.edu>
Sent : Tuesday, August 3, 2004 10:21 AM
To : GBUSA911@HOTMAIL.COM
Subject : walleye questions
| | | Inbox
Ohio does not stock walleyes in Lake Erie. We rely entirely on natural reproduction,since normally this will be what the lake will support in a given spring- based on the productivity of the food chain, which is tied to precipitation levels, turbidity and water temperatures during the critical period when walleye fry switch from their yolk-sac to planktonic food.
To stock numbers that would appreciably affect the bottom line (harvest) in 3 to 4 years, it would cost millions of dollars annually with no guarentee of success if there wasn't enough prey out there to support additional fry.
As for the question of survival of tournament caught walleyes, we have found that deep caught fish must have their air (gas) bladders decompressed by fizzing with a hypodermic needle as soon as symptoms (tipping over/bloating) occur. Also, there's a better chance of survival when the lake is calm, so the fish are not banged around in the live wells. We saw numerous puncture marks from spines piercing other fish and bruising from being slammed into the walls of the live well during rough seas. The cooler the water is, the more oxygen it holds, and fewer fungal diseases are active, so survival is better early in the season vs. later.
Hope this helps- John Hageman, Manager, F.T. Stone Laboratory- Ohio State University, Put-in-Bay, Ohio
Hello Jerry,
Water depth aside, I am not aware of any published research on the effects
of angler catch and release on subsequent survival of walleye in Lake Erie.
Published studies on hooking mortality, or post-release mortality, for a
variety of fish species indicate that water temperature tends to be a major
factor (warmer the water, higher the mortality for all fishes). Other
factors, like water depth, hook type, handling time, weather conditions,
species of fish, and fishing technique are also important. Keep in mind
that this kind of research is difficult to do without introducing
experimental error, especially in large lakes, where released fish are often
retained in some kind of enclosure for evaluation, that in itself can stress
fish.
With respect to your specific questions:
1.) From our monitoring experience with walleye tournaments in Ohio waters
of Lake Erie, we believe that most walleyes retained in live wells for
several hours under normal lake conditions will not survive when released.
Therefore, we do not recommend catch-release for walleye tournaments on Lake
Erie. We believe that most walleye caught and immediately released will
survive unless foul-hooked or mishandled. Healthy fish retained in
properly-maintained live wells under relatively calm lake conditions for
short time periods probably have a strong chance of surviving. In short,
Ohio law stipulates that any fish released must be alive and in good
condition. The decision to keep the fish is best made at time of capture.
2.) The Lake Erie walleye population is not maintained by stocking programs
and never has been. Walleye abundance fluctuates with annual levels of
natural reproduction, as influenced by a number of environmental factors
(temperature, wind, oxygen, food supply, predators/competitors)in ways that
are quite complex and difficult to understand and predict. Adult walleye
abundance is lower now than it was in the peak period of the mid to late
1980s because the reproductive pattern is different than it was back then,
when we measured above-average hatches in 4 of 5 years between 1982 and
1986. Walleye must survive at least two years in the lake to contribute to
fisheries, involving several life stages from eggs to fry to fingerlings to
older fish. It is much more complicated than simply "numbers of fry". The
addition of exotic species to the Lake Erie ecosystem has further
complicated our understanding of walleye reproduction.
3.) Ohio has not stocked walleyes in Lake Erie since 1971. There is no
interagency initiative to stock walleyes or to "match" what any agency does
in their jurisdiction for whatever purpose. Collectively, agencies are
dependent on natural reproduction to sustain fisheries lakewide.
Thanks for your interest in Lake Erie walleye and feel free to contact me if
you have other questions.
Roger L. Knight
Lake Erie Fisheries Program Administrator
ODNR Division of Wildlife
Sandusky Fisheries Research Station
305 E. Shoreline Drive
Sandusky OH 44870
(419) 625-8062
(419) 625-6272 fax
roger.knight@dnr.state.oh.us
-----Original Message-----
From: Navarro, John
Sent: Tuesday, August 03, 2004 8:55 AM
-----Original Message-----
From: gbusa911@hotmail.com [mailto:gbusa911@hotmail.com]
Sent: Monday, August 02, 2004 10:31 AM
To: Wildinfo
Subject: Comments from users
Gerald Roman at gbusa911@hotmail.com
I need your best biologist/researcher for the Erie Walleye to set the record
straight on the killing/releas of walleyes from deep water. PREFERABLY, I
WILL NEED FACTUAL, DOCUMENTED RESEARCH. This will be worth your time as it
is a topic of controversy for years that needs to be addressed on all major
boards.
Question:
1. When a tournament or fisherman of L. Erie and inland bodies of water
catch walleyes, put them in their live-well, run around the lake, can they
survive a release and what % if any? What research do you have to make your
point? Can I get a copy of it?
2. With the complex eco system of Erie(zebras, gobies, steelies the eating
machine, perch) and the boom of perch, why have the walleye gone down-hill
since 1970 when it is stated that stocking is more important than the spring
hatch? Does the lake simply get less fry than 30 years ago?
3. How many fry are stocked today compared to 1970? And, is PA matching the
fry amount?
GB&GBUSA,
Jerry
412 486 6133
| | | | | Inbox
GB&GBUSA,
Jerry
Below are responses to your Lake Erie questions. Please let me know if you need anything clarified or if you have any further questions.
Also, I would appreciate it if you could give me a link to any message boards that you post the responses on. I'm always interested in anglers' responses to our information and I would be interested in following the boards that you post on.
Take care,
Travis
Travis Hartman
Fisheries Biologist
Ohio Department of Natural Resources
Division of Wildlife
Sandusky Fish Research Unit
305 E. Shoreline Dr.
Sandusky, Ohio 44870
Phone: 419-625-8062
Fax: 419-625-6272
Travis.Hartman@dnr.state.oh.us
Question:
1. When a tournament or fisherman of L. Erie and inland bodies of water catch walleyes, put them in their live-well, run around the lake, can they survive a release and what % if any? What research do you have to make your point? Can I get a copy of it?
Iowa, Wisconsin, Minnesota and Ohio have all studied walleye tournament mortality at the time of weigh-ins and also delayed mortality after release.
The following is a summary of various studies as reported in the American Fisheries Society/North Central Division Walleye Technical Committee 2000 summer workshop notes:
Iowa, Mississippi River- Weigh-in mortality varied from less than 1% to 24%. 5 day delayed mortality ranged from 37% to 78% (55.8% average). Important factors affecting survival included livewell oxygen concentration and water temperatures.
Iowa, Lake Rathbun- Mortality at the time of weigh-in was 3%, but delayed mortality after 4 days was 76%.
Wisconsin, Winnebago system- Delayed mortality after 48 hours was 22% for fish that were not fizzed, 76% for fizzed fish, and 4% for a control group of fish that was caught by electroshocking and was not fizzed.
Ohio, Lake Erie- The PWT tournaments attempted live-release tournaments in '91, '92 and '93. 1991 was held during a calm period. 1,597 walleye were fizzed with 1% mortality at 20 hours. Mortality at 6 months after the tournament was estimated at an additional 3%. The 1992 PWT was held during 3 to 6 feet waves. Mortality for non-fizzed fish was 100% after 9 days, compared to 53% mortality for fizzed fish. Fish that died in 1992 were found to have spine-induced abdominal cavity puncture wounds from being held in livewells in rough seas. During the 1993 PWT over 2,000 fish were fizzed resulting in low immediate mortality, but delayed mortality was found to be high in the following days.
Minnesota published a Mille Lacs Lake walleye tournament study in the North American Journal of Fisheries Management (Goeman, T. J. 1991. Walleye mortality during a live-release tournament on Mille Lacs, Minnesota. North American Journal of Fisheries Management 11: 57-61). The Mille Lacs Lake results were as follows:
Mortality at the time of weigh-in 1.0 to 6.2%.
Delayed mortality after 5 days ranged from 5.7% to 47.1%.
Total tournament mortality, including all tournament days (both weigh-in and delayed mortality), was estimated at 40%.
The three factors that appeared to have the most impact on survival were weigh-in stress, weather conditions and density of fish in the boats' livewells. Of the fish that died the sex ratio was nearly 50:50 and there was not a relationship between fish size and probability of survival.
Summary of tournament research results:
It's clear from all of the tournaments studied that delayed mortality is higher than mortality observed at weigh-ins. The severity of delayed mortality seems to be strongly linked to wave conditions and surface temperature during the tournament. Larger waves and higher temperatures reduce the likelihood of survival of released fish. It is not clear if fizzing improves the survival rate of released fish.
2. With the complex eco system of Erie (zebras, gobies, steelies the eating machine, perch AND MANY MORE THAT CAN COME DAYLY) and the boom of perch, why have the walleye gone down-hill since 1970 when it is stated that stocking is more important than the spring hatch? Does the lake simply get less fry than 30 years ago? wHY THEN AND NOT NOW?
Based on walleye population estimates (adult fish, age-2 and older) by the Walleye Task Group of the Great Lakes Fishery Commission's Lake Erie Committee the population was at its largest in 1988 at around 70 million fish. Since 1997 the population has fluctuated between 16 and 29 million fish. The current population estimate for 2004 is just over 19 million. The Lake Erie walleye population is almost solely supported by natural reproduction, most of which takes place on the Ohio reef complex (Camp Perry firing range) and in the Maumee, Sandusky and Grand Rivers. Minimal stocking occurs in Pennsylvania and New York, but those stocked fish realistically don't make a population-level contribution. The stockings might influence localized areas, but stocking alone would never support walleye sportfishing on Lake Erie.
The Lake Erie walleye fishery is very year class dependant. Multiple strong year classes within a few years of each other lead to good fishing. The trend since the mid '90's has been an occasional average year class surrounded by poor to non-existent year classes. Right now the fishery is dominated by the '99 and 2001 year classes with larger fish coming from the '96, '94, '93, '91 and '90 year classes. Female walleye larger than 27" and male walleye larger than 24" are usually 10 years old or older. We are finding that walleye can live in excess of 20 years, with fish from the exceptional 1982 year class still occasionally being caught.
While the size and survival rate of each year's hatch is mostly determined by weather conditions the management of allowable harvest of the resulting year classes is up to management agencies around the lake. Reduced Total Allowable Catches (the number of walleye that are allowed to be harvested each year by each management agency, i.e. ODNR, PA FBC, MDNR, OMNR, NYDEC) have been agreed upon by all agencies to help conserve the walleye population during this period of lower population numbers. The enormous year class from 2003 will help to fuel the population in coming years.
3. How many fry are stocked today compared to 1970? And, is PA matching the fry amount?
Currently there is very limited walleye stocking in Lake Erie. A Pennsylvania walleye club stocks approximately 800,000 very early stage larvae into Presque Isle Bay each spring. The survival of the stocked fish and their contribution to the population has not been documented. New York is currently attempting to rehabilitate walleye in the Buffalo River by stocking 2" fingerlings in the river for the next 5 to 7 years. This was the first year and 26,000 fingerlings were stocked. The stockings will not continue past the 5 to 7 year time period. The stockings will be evaluated to find out whether or not a reproducing population can be re-established in the Buffalo River.
During the years that the Put-In-Bay hatchery was in operation ODNR did stock walleye in Lake Erie. There was not any proof that the stocked walleye actually contributed to the population. Lake Erie has plenty of spawning habitat between the reefs and the rivers. In years that the conditions are right the native walleye produce incredible hatches. In the years that we have year class failures the survival of the hatch is reduced by weather conditions. In those poor weather years that did not support the hatch stocked fish would also likely face high mortality. There will not be any large scale stocking of walleye in Lake Erie any time soon.
Wildinfo.Fish@dnr.state.oh.us
Jerry,
Water depth aside, I am not aware of any published research on the effects
of angler catch and release on subsequent survival of walleye in Lake Erie.
Published studies on hooking mortality, or post-release mortality, for a
variety of fish species indicate that water temperature tends to be a major
factor (warmer the water, higher the mortality for all fishes). Other
factors, like water depth, hook type, handling time, weather conditions,
species of fish, and fishing technique are also important. Keep in mind
that this kind of research is difficult to do without introducing
experimental error, especially in large lakes, where released fish are often
retained in some kind of enclosure for evaluation, that in itself can
stress
fis!
h.
With respect to your specific questions:
1.) From our monitoring experience with walleye tournaments in Ohio waters
of Lake Erie, we believe that most walleyes retained in live wells for
several hours under normal lake conditions will not survive when released.
Therefore, we do not recommend catch-release for walleye tournaments on Lake
Erie. We believe that most walleye caught
and immediately released will
survive unless foul-hooked or mishandled. Healthy fish retained in
properly-maintained live wells under relatively calm lake conditions for
short time periods probably have a strong chance of surviving. In short,
Ohio law stipulates that any fish released must be alive and in good
condition. The decision to keep the fish is best made at time of capture.
2.) The Lake Erie walleye population is not maintained by stocking
programs
and never has been. Walleye abundance fluctuates with annual levels of
natural reproduction, as influenced by a number of environmental factors
(temperature, wind, oxygen, food supply, predators/competitors)in ways that
are quite complex and difficult to understand and predict. Adult walleye
abundance is lower now than it was in the peak period of the mid to late
1980s because the reproductive pattern is different than it was back then,
when we measured above-average hatches in 4 of 5 years between 1982 and
1986. Walleye must survive at least two years in the lake to contribute to
fisheries, involving several life stages from eggs to fry to fingerlings to
older fish. It is much more complicated than simply "numbers of fry". The
addition of exotic species to the Lake Erie ecosystem has further
complicated our understanding of walleye reproduction.
3.) Ohio has not
stocked walleyes in Lake Erie since 1971. There is no
interagency initiative to stock walleyes or to "match" what any agency does
in their jurisdiction for whatever purpose. Collectively, agencies are
dependent on natural reproduction to sustain fisheries lakewide.
-----Original Message-----
From: gbusa911@hotmail.com [mailto:gbusa911@hotmail.com]
Sent: Monday, August 02, 2004 10:31 AM
To:
Wildinfo
Subject: Comments from users
Gerald Roman at gbusa911@hotmail.com
I need your best biologist/researcher for the Erie Walleye to set the
record
straight on the killing/releas of walleyes from deep water. PREFERABLY, I
WILL NEED FACTUAL, DOCUMENTED RESEARCH. This will be worth your time as it
is a topic of controversy for years that needs to be addressed on all major
boards.
Question:
1. When a tournament or fisherman of L. Erie and inland bodies of water
catch walleyes, put them in their live-well, run around the
lake, can they
survive a release and what % if any? What research do you have to make your
point? Can I get a copy of it?
2. With the complex eco system of Erie(zebras, gobies, steelies the eating
machine, perch) and the boom of perch, why have the walleye gone down-hill
since 1970 when it is stated that stocking is more important than the spring
hatch? Does the
lake simply get less fry than 30 years ago?
3. How many fry are stocked today compared to 1970? And, is PA matching the
fry amount?
GB&GBUSA,
Jerry
412 486 6133
Hello Jerry,
Water depth aside, I am not aware of any published research on the effects
of angler catch and release on subsequent survival of walleye in Lake Erie.
Published studies on hooking mortality, or post-release mortality, for a
variety of fish species indicate that water temperature tends to be a major
factor (warmer the water, higher the mortality for all fishes). Other
factors, like water depth, hook type, handling time, weather conditions,
species of fish, and fishing
technique are also important. Keep in mind
that this kind of research is difficult to do without introducing
experimental error, especially in large lakes, where released fish are often
retained in some kind of enclosure for evaluation, that in itself can stress
fish.
With respect to your specific questions:
1.) From our monitoring experience with walleye tournaments in
Ohio waters
of Lake Erie, we believe that most walleyes retained in live wells for
several hours under normal lake conditions will not survive when released.
Therefore, we do not recommend catch-release for walleye tournaments on Lake
Erie. We believe that!
most wa
lleye caught and immediately released will
survive unless foul-hooked or mishandled. Healthy fish retained in
properly-maintained live wells under relatively calm lake conditions for
short time periods probably have a strong chance of surviving. In short,
Ohio law stipulates that any fish released must be alive and in good
condition. The decision to keep the fish is best made at time of capture.
2.) The Lake Erie walleye population is not maintained by
stocking programs
and never has been. Walleye abundance fluctuates with annual levels of
natural reproduction, as influenced by a number of environmental factors
(temperature, wind, oxygen, food supply, predators/competitors)in ways that
are quite complex and difficult to understand and predict. Adult walleye
abundance is lower now than it was in the peak period of the mid to late
1980s because the reproductive pattern is different than it was back then,
when we measured above-average hatches in 4 of 5!
years b
etween 1982 and
1986. Walleye must survive at least two years in the lake to contribute to
fisheries, involving several life stages from eggs to fry to fingerlings to
older fish. It is much more complicated than simply "numbers of fry". The
addition of exotic species to the Lake Erie ecosystem has further
complicated our understanding of walleye reproduction.
3.) Ohio has not stocked walleyes in Lake Erie since 1971. There is
no
interagency initiative to stock walleyes or to "match" what any agency does
in their jurisdiction for whatever purpose. Collectively, agencies are
dependent on natural reproduction to sustain fisheries lakewide.
Thanks for your interest in Lake Erie walleye and feel free to contact me if
you have other questions.
Roger L. KnightLake Erie Fisheries Program AdministratorODNR Division of WildlifeSandusky Fisheries Research Station305 E. Shoreline DriveSandusky OH 44870(419) 625-8062(419) 625-6272 faxroger.knight@dnr.state.oh.us
Hageman <hageman.2@osu.edu>
Sent : Tuesday, August 3, 2004 10:21 AM
To : GBUSA911@HOTMAIL.COM
Subject : walleye questions
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Ohio does not stock walleyes in Lake Erie. We rely entirely on natural reproduction,since normally this will be what the lake will support in a given spring- based on the productivity of the food chain, which is tied to precipitation levels, turbidity and water temperatures during the critical period when walleye fry switch from their yolk-sac to planktonic food.
To stock numbers that would appreciably affect the bottom line (harvest) in 3 to 4 years, it would cost millions of dollars annually with no guarentee of success if there wasn't enough prey out there to support additional fry.
As for the question of survival of tournament caught walleyes, we have found that deep caught fish must have their air (gas) bladders decompressed by fizzing with a hypodermic needle as soon as symptoms (tipping over/bloating) occur. Also, there's a better chance of survival when the lake is calm, so the fish are not banged around in the live wells. We saw numerous puncture marks from spines piercing other fish and bruising from being slammed into the walls of the live well during rough seas. The cooler the water is, the more oxygen it holds, and fewer fungal diseases are active, so survival is better early in the season vs. later.
Hope this helps- John Hageman, Manager, F.T. Stone Laboratory- Ohio State University, Put-in-Bay, Ohio
Hello Jerry,
Water depth aside, I am not aware of any published research on the effects
of angler catch and release on subsequent survival of walleye in Lake Erie.
Published studies on hooking mortality, or post-release mortality, for a
variety of fish species indicate that water temperature tends to be a major
factor (warmer the water, higher the mortality for all fishes). Other
factors, like water depth, hook type, handling time, weather conditions,
species of fish, and fishing technique are also important. Keep in mind
that this kind of research is difficult to do without introducing
experimental error, especially in large lakes, where released fish are often
retained in some kind of enclosure for evaluation, that in itself can stress
fish.
With respect to your specific questions:
1.) From our monitoring experience with walleye tournaments in Ohio waters
of Lake Erie, we believe that most walleyes retained in live wells for
several hours under normal lake conditions will not survive when released.
Therefore, we do not recommend catch-release for walleye tournaments on Lake
Erie. We believe that most walleye caught and immediately released will
survive unless foul-hooked or mishandled. Healthy fish retained in
properly-maintained live wells under relatively calm lake conditions for
short time periods probably have a strong chance of surviving. In short,
Ohio law stipulates that any fish released must be alive and in good
condition. The decision to keep the fish is best made at time of capture.
2.) The Lake Erie walleye population is not maintained by stocking programs
and never has been. Walleye abundance fluctuates with annual levels of
natural reproduction, as influenced by a number of environmental factors
(temperature, wind, oxygen, food supply, predators/competitors)in ways that
are quite complex and difficult to understand and predict. Adult walleye
abundance is lower now than it was in the peak period of the mid to late
1980s because the reproductive pattern is different than it was back then,
when we measured above-average hatches in 4 of 5 years between 1982 and
1986. Walleye must survive at least two years in the lake to contribute to
fisheries, involving several life stages from eggs to fry to fingerlings to
older fish. It is much more complicated than simply "numbers of fry". The
addition of exotic species to the Lake Erie ecosystem has further
complicated our understanding of walleye reproduction.
3.) Ohio has not stocked walleyes in Lake Erie since 1971. There is no
interagency initiative to stock walleyes or to "match" what any agency does
in their jurisdiction for whatever purpose. Collectively, agencies are
dependent on natural reproduction to sustain fisheries lakewide.
Thanks for your interest in Lake Erie walleye and feel free to contact me if
you have other questions.
Roger L. Knight
Lake Erie Fisheries Program Administrator
ODNR Division of Wildlife
Sandusky Fisheries Research Station
305 E. Shoreline Drive
Sandusky OH 44870
(419) 625-8062
(419) 625-6272 fax
roger.knight@dnr.state.oh.us
-----Original Message-----
From: Navarro, John
Sent: Tuesday, August 03, 2004 8:55 AM
-----Original Message-----
From: gbusa911@hotmail.com [mailto:gbusa911@hotmail.com]
Sent: Monday, August 02, 2004 10:31 AM
To: Wildinfo
Subject: Comments from users
Gerald Roman at gbusa911@hotmail.com
I need your best biologist/researcher for the Erie Walleye to set the record
straight on the killing/releas of walleyes from deep water. PREFERABLY, I
WILL NEED FACTUAL, DOCUMENTED RESEARCH. This will be worth your time as it
is a topic of controversy for years that needs to be addressed on all major
boards.
Question:
1. When a tournament or fisherman of L. Erie and inland bodies of water
catch walleyes, put them in their live-well, run around the lake, can they
survive a release and what % if any? What research do you have to make your
point? Can I get a copy of it?
2. With the complex eco system of Erie(zebras, gobies, steelies the eating
machine, perch) and the boom of perch, why have the walleye gone down-hill
since 1970 when it is stated that stocking is more important than the spring
hatch? Does the lake simply get less fry than 30 years ago?
3. How many fry are stocked today compared to 1970? And, is PA matching the
fry amount?
GB&GBUSA,
Jerry
412 486 6133
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