Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
North Carolina ◽  
International Symposium ◽  
Maximum Size ◽  
Large Fish ◽  
Blue Catfish ◽  
Conservation Ecology ◽  
Size Limit ◽  
Catch And Release ◽  
The North ◽  
Gill Net

<em>Abstract</em>.—Blue catfish <em>Ictalurus furcatus </em>were introduced into North Carolina reservoirs in the mid-1960s and have recently become a popular target for anglers pursuing large catfish. In 2008, the North Carolina Wildlife Resources Commission enacted a maximum size limit for blue catfish at Badin Lake and Lake Norman where only one fish greater than 813 mm could be harvested daily. Surveys indicated that few fish larger than 813 mm were present in either system and that the time to reach the size limit was 12 years in Badin Lake and 20 years in Lake Norman, on average. Although few large fish were present in either system, tournament anglers at Lake Norman kept larger fish in a higher proportion than found in gill-net surveys or harvested during a recent creel survey. Modeling results suggested that the regulation would have little or no impact on increasing the number of large catfish in either population. However, the regulation will protect some rare fish that grow to the maximum size limit and potentially allow recapture opportunities if catch-and-release mortality is low.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
International Symposium ◽  
Size Structure ◽  
Pylodictis Olivaris ◽  
Social Event ◽  
Conservation Ecology ◽  
Party Size ◽  
Catch And Release ◽  
Flathead Catfish ◽  
Creel Survey ◽  
Total Effort

<em>Abstract</em>.—Hand grabbing for catfish has been practiced in Mississippi for many years; however, few studies have addressed this fishing technique. Ross Barnett Reservoir is a<em> Abstract</em>.—Hand grabbing for catfish has been practiced in Mississippi for many years; however, few studies have addressed this fishing technique. Ross Barnett Reservoir is a 13,360-ha impoundment located in central Mississippi that supports a substantial hand grabbing fishery. A roving creel survey was conducted during the 2007 and 2008 Mississippi hand grabbing season (May 1–July 15). Objectives were to estimate catch, harvest, and effort of hand grabbers and to solicit information concerning techniques used by these anglers. A total of 37 parties was interviewed, consisting of 150 total anglers. Seventy percent of the parties interviewed targeted flathead catfish <em>Pylodictis olivaris</em>. Ninety-five percent of the parties used a probe, and all parties fished boxes located at depths of 1–2 m. Average party size was four anglers, indicating that hand grabbing is a social event. For 2007 and 2008, anglers spent an estimated 4,424 and 5,259 h hand grabbing, respectively. An estimated 3,313 and 2,589 catfish were harvested in 2007 and 2008, respectively. Based on size structure of harvested catfish, hand grabbing anglers at Ross Barnett Reservoir do not appear to be size-selective. Most anglers were harvest-oriented, with catch-and-release estimates making up only 12% and 9%, respectively. Future creel surveys should be directed at the total effort allocated toward catfishing, in an effort to determine the effect of hand grabbing on Ross Barnett Reservoir.

Scenario-based analyses evaluate potential outcomes of proposed regulatory changes in recreational fishery

2019 ◽  
Vol 77 (6) ◽  
pp. 2333-2343 ◽  
Author(s):  
Alyssa S Thomas ◽  
Taciano L Milfont ◽  
Michael C Gavin
Keyword(s):  
New Zealand ◽  
Management Strategies ◽  
Maximum Size ◽  
Potential Outcomes ◽  
Effective Management ◽  
Large Fish ◽  
Recreational Fisheries ◽  
Size Limit ◽  
Regulatory Changes ◽  
Regulation Change

Abstract Understanding current and predicting future behaviour of fishers is fundamental to designing effective management strategies. The management of most recreational fisheries requires releasing fish not meeting size or daily limits, and assuming the majority survive. In the Marlborough Sounds, New Zealand, a maximum size limit imposed on the blue cod (Parapercis colias) fishery aimed to achieve a more balanced sex ratio for this hermaphroditic species. We tested three alternative size limit scenarios (current, increased, and no maximum size) in a study with recreational fishers (N = 420) to investigate whether regulation change would influence their intentions to discard fish and fishing satisfaction. Increasing or eliminating the maximum size led to lower discard intentions and greater fishing satisfaction, suggesting strategies to achieve both management goals (e.g. more large fish) and increased fisher satisfaction (potentially increasing compliance). More broadly, the results demonstrate the benefits of using scenarios to evaluate potential regulatory changes prior to implementation.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
International Symposium ◽  
Pylodictis Olivaris ◽  
Blue Catfish ◽  
Conservation Ecology ◽  
Flathead Catfish ◽  
Tag Loss ◽  
Reward Value ◽  
Exploitation Rate ◽  
Time Correction ◽  
Regulation Changes

<em>Abstract</em>.—The Missouri Department of Conservation suspected that blue catfish <em>Ictalurus furcatus </em>and flathead catfish <em>Pylodictis olivaris </em>were being heavily exploited by anglers in 22,539-ha Harry S. Truman Reservoir in west-central Missouri. A reward tag study was initiated in 2004 to determine angler exploitation rates for both species. Three hundred blue catfish ≥ 482 mm total length (TL) and 194 flathead catfish ≥ 508 mm TL were equipped with transbody Carlin dangler reward tags in 2004 and 2005, respectively. All reward tags displayed a reward value of US$50. A 5-year post-tagging estimate of annual exploitation (<em>u</em>) was calculated with a 25% annual correction for angler nonreporting and a one-time correction for tag loss. The estimated annual exploitation rates for blue catfish ranged from 25.5% to 33.4% with a mean of 28.8%. The estimated cumulative exploitation rate (<EM>U</EM>) at 5-years post-tagging was 81.7% for all sizes of tagged blue catfish and 92.4% for tagged blue catfish ≥ 610 mm TL. The estimated annual exploitation rates for flathead catfish ranged from 0% to 3.9% with a mean of 1.8%. The estimated cumulative exploitation rate at 5-years post-tagging for flathead catfish was 8.8%. These exploitation rates indicate that blue catfish are being heavily exploited while flathead catfish are not. Of all the reward tagged blue catfish that were reported by anglers, 7% were reported as released while 22% of the reported flathead catfish were released. These results are being used to examine possible regulation changes to protect the blue catfish fishery at Truman Reservoir.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
International Symposium ◽  
Channel Catfish ◽  
Capture Efficiency ◽  
Ictalurus Furcatus ◽  
Blue Catfish ◽  
Conservation Ecology ◽  
Incidental Capture ◽  
Coastal Rivers ◽  
Second International

<em>Abstract</em>.—Use of trotlines to collect data on catfish populations can lead to incidental capture of endangered turtles. We evaluated the effectiveness of Zote© soap as a way to prevent capture of turtles on trotlines fished in coastal rivers of Mississippi and compared capture efficiency of cut bait and Zote© soap in research ponds. More than 11,000 hooks baited with Zote© soap were fished overnight in six coastal rivers of Mississippi, resulting in the capture of zero turtles, 193 blue catfish <em>Ictalurus furcatus</em>, and 462 channel catfish <em>I. punctatus</em>. Direct comparisons with other baits were not conducted in the coastal rivers because capture of a single endangered turtle would have resulted in revocation of our sampling permit. Therefore, comparisons of cut bait and Zote© soap were conducted in research ponds. The fi rst trial fished 440 hooks each of cut bait and Zote© soap. Cut bait and Zote© soap collected one and zero turtles, respectively, while each bait captured 48 channel catfi sh. The second trial fished 120 hooks each of cut bait and Zote© soap. Cut bait and Zote© soap collected two and zero turtles, respectively, and 15 and 8 channel catfish, respectively. A Mann–Whitney U-test indicated no signifi cant difference between bait type in number of catfish or turtles captured in either trial. While statistical differences in turtle catch between bait types were not found, preventing any capture of endangered turtles in the field is a high priority and our results indicated that use of Zote© soap provides the best method for eliminating turtle capture on trotlines in coastal rivers of Mississippi.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
International Symposium ◽  
Size Structure ◽  
River System ◽  
Population Characteristics ◽  
Blue Catfish ◽  
Growth And Survival ◽  
Conservation Ecology ◽  
Flathead Catfish ◽  
Management Actions ◽  
Catch Rates

<em>Abstract</em>.—Catfish are popular recreational fish in Alabama, and management interest has been rising. We hypothesized that tailwater habitat more closely resembling lotic conditions would provide more suitable conditions for catfishes compared to impounded habitats. We examined and compared population characteristics, including abundance, age and size structure, growth, and survival of blue catfish <em>Ictalurus furcatus</em>, channel catfish <em>I. punctatus</em>, and flathead catfish <em>Pylodictis olivaris</em> between tailwater and reservoir habitats in a section of the Coosa River in 2001–2002. Coosa River system tailwater habitats appear to generally provide higher quality environments for abundance and growth of catfishes than reservoir habitat, although results were often not consistent among species. We found no differences for many comparisons of stock descriptors between tailwater and reservoir habitat. We found that blue catfish were larger (48 mm total length larger) and flathead catfish electrofishing catch rates were higher (13 fish/h greater) in tailwater areas. Catfish populations in the Coosa River were characterized by slow growth and high longevity, findings in accord with other recent otolith-based age analyses from populations in the Southeast. All species had moderate to high annual survival (57–88%), likely indicating light exploitation levels. Catfish populations in this section of the Coosa River appear robust, and the tendency for these dam tailwaters to have higher quality catfish populations may warrant management actions to enhance/sustain these fisheries.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
International Symposium ◽  
Relative Abundance ◽  
Wildlife Conservation ◽  
Age And Growth ◽  
Mortality Data ◽  
Blue Catfish ◽  
Sampling Methodology ◽  
Conservation Ecology ◽  
Slow Growing ◽  
Annual Mortality

<em>Abstract</em>.—Management of blue catfish <em>Ictalurus furcatus</em> populations is an emerging focus for state fish and wildlife agencies as catfish anglers have shown a growing interest in trophy fishing. As blue catfish sampling methodology has improved, management of blue catfish fisheries has become a greater priority in some states. The Oklahoma Department of Wildlife Conservation (ODWC) has collected abundance, age and growth, and mortality data on blue catfish from 14 reservoirs statewide. Electrofishing surveys indicated that blue catfish populations are dominated by slow-growing fish less than 400 mm total length (TL) and average 24% total annual mortality. In addition, relative abundance of ≥762 mm TL blue catfish in the angler creel (8%) greatly exceeds that in population samples (<1%). In 2009, ODWC recommended a statewide regulation limiting harvest of blue catfish greater than 762 mm TL to one fish per day while maintaining the daily limit of 15 fish per day. The proposal met with moderate opposition through the regular regulation review process but was approved by the Oklahoma Wildlife Commission. Legislative opposition to the proposal subsequently developed, and a resolution was introduced to rescind the regulation but ultimately failed. A regulation restricting blue catfish harvest to 15 fish daily with only 1 fish ≥762 mm TL went into effect on January 1, 2010.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
International Symposium ◽  
Mail Survey ◽  
Attitude Scale ◽  
Policy Formation ◽  
Large Fish ◽  
Conservation Ecology ◽  
Related Attitude ◽  
Second International

<em>Abstract</em>.—Previous research indicates that hand grabbling does not negatively affect catfish populations in Mississippi, but hand grabbling is restricted to a season to control harvest of large fish. We conducted a mail survey from October to December 2008 to compare Mississippi hand grabbler and rod-and-reel catfish angler sociodemographics, fishing characteristics, participation patterns, and catch-related attitudes. A catch-related attitude scale was used to measure angler’s evaluation of catching fish in four constructs (catching something, catching numbers, catching large fish, and retaining fish). Results indicated that hand grabblers had stronger attitudes toward catching large fish, but rod-and-reel catfish anglers had stronger attitudes toward catching numbers. We explained that possible differences in catch-related attitudes and other characteristics were due to hand grabblers being a more specialized subworld of catfish anglers. Understanding differences in characteristics and processes through which these subworlds differed can assist with policy formation, especially if competition over resources (e.g., large, trophy catfishes) intensifies.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
Size Structure ◽  
Management Strategies ◽  
Northwestern Part ◽  
Blue Catfish ◽  
Conservation Ecology ◽  
Catch Data ◽  
Annual Survey ◽  
Gill Net ◽  
Glass Slides ◽  
Similar Survey

<em>Abstract</em>.—In Georgia, blue catfish <em>Ictalurus furcatus</em> are native in the Coosa River drainage in the northwestern part of the state. However, they were first detected outside this range during an annual gill net survey of Lake Sinclair conducted by the Georgia Department of Natural Resources in 1996, then again in a similar survey of Lake Oconee during 1997. Catch of blue catfish in annual surveys of Lake Oconee continued to increase, but demographics of the populations are unknown. We used annual survey data for the period 1989–2009 to identify trends in catch of blue catfish in the lake. Age and size structure of the blue catfish population in Lake Oconee was assessed based on catch data from the 2008 survey. Mean length for blue catfish captured (<em>n</em> = 121) was 330 mm (SD = 132 mm), and mean weight was 468 g (SD = 683.9 g); the largest fish was 740 mm and weighed 5078 g. Otoliths from the blue catfish collected were cross-sectioned, mounted on glass slides, and examined under a dissecting microscope, and annuli on each section were counted independently by two readers. Catch data indicated that blue catfish catch increased rapidly after 1997. Seven year-classes (2001–2007) were represented in the 2008 sample, and most fish were from the 2003 year-class (mean age: 3.7 years; SD = 1.4 years). These data document a rapidly expanding blue catfish population in Lake Oconee and could serve as the basis for developing management strategies in this reservoir system and others across North America where blue catfish are expanding their range.

Biology and Management of Dogfish Sharks

2009 ◽  
Keyword(s):  
North Carolina ◽  
South Carolina ◽  
Coastal Waters ◽  
Outer Banks ◽  
The North ◽  
Gill Net ◽  
Cape Hatteras ◽  
Long Bay ◽  
Time Of Year ◽  
Separate Population

Abstract.—Little information is available about the coastal distribution of spiny dogfish <em>Squalus acanthias </em>south of Cape Hatteras, North Carolina, and whether these fish are an extension of the population that overwinters in continental shelf waters off the North Carolina Outer Banks north of Cape Hatteras, or a separate population that remains south of Cape Hatteras. A coastal roaming survey was conducted in February and March 1999 from south of Cape Hatteras to the South Carolina state line to estimate the number of dogfish in coastal waters. Fish aggregations were located by sonar, and a commercial-grade sink gill net of seven different mesh sizes was deployed in waters to assess whether the aggregations were dogfish. Six large dogfish aggregations were located in shallow (10–16 m) coastal waters of Raleigh Bay, Onslow Bay, and Long Bay, covering an estimated surface area of about 66,922 ha. Two additional sets marked by sonar were not dogfish aggregations. No dogfish were caught in exploratory deepwater sets (46–55 m). Using a sensitivity analysis, total population size of all aggregations was estimated at 1.102 to 2.223 million individuals or 2.470 to 4.984 million kg. The sex ratio was 27.1:1 females to males. Aggregations were located near the bottom at a temperature range of 10.4°C to 15.7°C. Temperatures varied little vertically through the water column; laterally temperatures varied by less than 1°C for five of six aggregations. The largest aggregation, in Raleigh Bay, was exposed to the greatest spatial variability in temperature (3.6°C across 15,135 ha). This is perhaps a result of its proximity to the Gulf Stream at this time of year. We believe that dogfish south of Cape Hatteras during the winter are a small portion, probably less than 1%, of the U.S. migratory stock.

Sign in / Sign up

Export Citation Format

Share Document