GULF COAST SHARK CENSUS TOURNAMENT

Transcription

1 GULF COAST SHARK CENSUS TOURNAMENT FINAL REPORT Submitted to: Columbus Zoological Park Association, Inc Riverside Drive P.O. Box 400 Powell, Ohio Submitted by: Center for Shark Research Mote Marine Labcratory 1600 Ken Thompson Parkway Sarasota, FL Robert E. Hueter, Ph.D. Director, MML Center for Shark Research November 21, 1995 MOTE TECHNICAL REPORT 450

2 1600 KEN THOMPSON PARKWAY SARASOTA, FLORIDA PHONE: (94 1) FAX: (941) INTERNET: "A nonprofit organization dedicated to excellence in marine sciences" November 21, 1995 Animal Management, Health and Scientific Studies Committee Columbus Zoological Park Association, Inc Riverside Drive P.O. Box 400 Powell, Ohio Dear Committee Members: I am pleased to report that our 1995 conservation and research project entitled "Gulf Coast Shark Census Tournament," which was funded in part by your organization, was an overwhelming success. Enclosed is our final report on this project, including a summary of the objectives, activities and results. Also enclosed is a copy of the project booklet used by the project participants. Attached to this letter is a copy of the final financial report for this project, with the expenditures using the Columbus Zoo grant highlighted. The $1,000 provided by your organization was used to purchase special shark tags for the project, as called for in our agreement. All funds were expended and are listed under the category "Research supplies" in our financial report. As you can see, the total cost of this project was over $12,000; the $1,000 provided by the Zoo was critical to our fundraising efforts to continue. this important program. The Zoo was gratefully acknowledged in all press releases on this project. I want to thank you once again for your generous support of our efforts. As an independent, nonprofit research and education organization, Mote Marine Laboratory is not a part of any governmental or university body, and so must support all of its research and conservation activities with extramural support. Your help in this work is most appreciated. I hope that you continue to fmd our conservation-oriented activities worthy of support. To that end, I would be interested to learn how we can continue this relationship and perhaps expand the scope of work supported by your organization. Please let me know if I can provide any further information. Thank you again and I look forward to hearing back from you soon. Cordially, Gl~ ~t-t---q2 Robert E. Hueter, Ph.D. Senior Scientist & Director MML Center for Shark Research Encls. MICHAEL T. MARTIN CHAIRMAN OF THE BOARD WILLIAM A. MOTE PRESIDENT KUMAR MAHADEVAN, Ph.D. EXECUTIVE DIRECTOR

3 MOTE MARINE LABORA TORY'S ANNUAL GULF COAST SHARK CENSUS "The world's only 100% catch-and-release shark tournament for research... where only the information is landed!" Depletion of shark populations worldwide, and the resulting need for shark fishery management, has called for a change in angler ethics as well as a new public awareness of the resource value of sharks. Such changes can only come through effective education based on solid research. The annual Gulf Coast Shark Census, the world's only 100% catch-andrelease recreational shark tournament designed for research, has been an effective tool in bringing about these changes. The Gulf Coast Shark Census has fulfilled a dual role of education and research, at the same time allowing anglers to continue the enjoyment of their sport-but not at the expense of the resource. Creation of the tournament began in 1988, when a group of recreational shark fishermen from southwest Florida approached scientists at Mote Marine Laboratory in Sarasota with the desire to support shark research. The fishermen's initial idea was to stage a large "kill" tournament for sharks and donate the proceeds for shark research projects. It would have been inconsistent with the Laboratory's commitment to marine resource conservation to sanction this event on its behalf, but Mote shark biologists saw an opportunity to turn the idea around at a time when concern was building over depleted shark populations. Although some "kill" tournaments had yielded important samples for scientific research, the condoning of simply killing sharks for sport-where little or none of the shark is used for any purpose, but simply discarded after being entered in the competition-was a thing of the past. The time for the sportfishing community to take some responsibility in wise use of the shark resource had come. Working with a tournament committee consisting of sportfishermen, local businessmen, and conservationists, MML scientists designed an innovative approach to the problem. The tournament would be 100% catch-and-release, and the scientists would retain control over the tournament design and rules. Not a single shark would be needlessly killed; instead, all sharks would be identified and measured, tagged when possible, and released. In this way, the tournament would serve as a proof-of-concept program for catch-and-release fishing for sharks. The collected data would be used to track local shark populations, leading to the "census" concept. Tag returns would serve to gauge catch-and-release mortality as well as provide migratory and age/growth inforniation. The fishermen would compete for prizes, and the event would be used to publicize the state of the shark resource and the importance of management measures, to preserve the viability of both the resource and the fishery. The concept was a success from that first year, steadily building a consensus of support through the years. The educational opportunities for the tournament grew each year as national media provided broader coverage of the story. Furthermore, with the advent of federal and state shark management measures that included bag limits and closed seasons, the tournament emerged as a unique demonstration project to test the feasibility of catch-andrelease fishing for sharks. 2

4 PROJECT GOALS The annual Gulf Coast Shark Census has the following major goals: ~ Assess the feasibility of catch-and-release programs for U.S. shark recreational fisheries, and evaluate the effects of this practice on the survivorship of sharks targeted by recreational fishermen. ~ Transform the efforts of recreational fishermen from" catch-and-kill" to catch-and-release of sharks where necessary and feasible, as well as promote tagging programs for all fishes, to conform with emerging management practices and serve as a model for similar programs throughout the nation. ~ Harness the energy of the recreational fishing community to collect long-term scientific data on species/size distributions, migration and growth, and catch per unit effort for sharks in the Gulf of Mexico. ~ Reward fishermen for participating in conservation and research-oriented fishing practices, instead of simply disallowing them from utilizing the resource. ~ Encourage conservation and wise management of our common resources by educating fishermen, resource managers, and the public at large on the importance of sharks as a marine resource. PROJECT ACCOMPLISHMENTS Accomplishments of the Gulf Coast Shark Census over its seven consecutive years of operation include the following: ~ Participation of over 860 registered anglers in the tournament ~ Education of thousands of anglers and the general public in shark identification and biology ~ Scientific data collected on over 3,700 sharks, all released alive after capture ~ Over 420 sharks tagged before release by scientists aboard tournament boats ~ Successful testing of shark de hooking devices and scientific assessment of shark survival after hook-and-release ~ Discovery of important nursery areas for several shark species ~ Establishment of a long-term database to track shark populations for scientists and fishery managers ~ Tournament conservation message spread worldwide through international media 3

5 1995 GULF COAST SHARK CENSUS TOURNAMENT RESULTS SUMMARY ~ 93 registered anglers participated; 71 (76%) caught-and-released at least one shark (compared with 104/62/60% in 1994 and 180/115/63% in 1993) ~ Data collected on a total of 956 sharks = most ever in the 7-year history of the Gulf Coast Shark Census Tournament ~ Average of 13.4 sharks caught per successful angler (8.5 in 1994) ~ 2,840.5 total line-hours of fishing effort reported by 65 anglers = approx. 3 line-hours per shark caught-and-released by average successful angler (approx. 4.0 line-hrs per shark in 1994; approx. 5.0 I-hrs per shark in 1993) ~ Average estimated size of shark < 4 feet total length; as in past years, small sharks like blacknose and young blacktip pups continue to dominate the catches ~ TAGGING: In 1995, MML scientists tagged 210 of the small sharks caught on 5 tournament boats = most ever tagged in the 7-year history of the tournament ~ BY SPECIES, the number of sharks tagged in the 1995 tournament were as follows: blacknose (Carcharhinus acronotus), 186; blacktip (C. limbatus), 14; bonnethead (Sphyrna tiburo), 6; spinner (C. brevipinna), 2; bull (C. /eucas), 1; and Atlantic sharpnose (Rhizoprionodon terraenovae), 1. ~ IN THE OVERALL MML SHARK RESEARCH PROGRAM, over 3,000 small sharks have been tagged, and approximately 15% of these have been tagged through the tournament since ~ RECAPTURES: Two recaptures of tagged sharks were rep'orted during the 1995 tournament: 1) Blacknose immature male tagged in Tampa Bay on June 28, 1993 during the 1993 tournament: recaptured during 1995 tournament two years and eight days later in almost exactly the same place where it had been tagged. It had grown approximately 8-1 2" in those two years. 2) Blacknose immature female tagged in Tampa Bay during the 1992 tournament (July 5, 1992): recaptured during 1995 tournament one week short of exactly three years at liberty, in which time it had grown exactly one foot in length. It was recaptured less than 3 miles from the tagging site. ~ These and other recaptures in the MML tagging program provide evidence that these sharks are returning to defined areas on an annual cycle. In the fall and winter, these sharks leave the area completely and are distributed offshore and to the south. But when they return in the spring and summer, they appear to navigate back to the same sites where they have been found in previous years. DATA FOLLOW ON THE LOCALITIES AND BIOLOGICAL INFORMATION ON SHARKS TAGGED DURING THE 1995 TOURNAMENT [REPRO. = stage of maturity where 1 = neonate, 1.5 = young-of-the-year, 2 = juvenile> 1 yr and 3 = adult; PC = precaudal length; FL = fork length; TL = total length; STL = stretch total length) 4

6 r t I CENSUS SAMPLING AREA 1- Cape Sable * CENSUS TAGGING LOCATIONS

7 MO DA COMMON NAME SEX REPRO. PC (em) FL (em) TL (em) STL (em) TAG # LOCATION 6 25 Blacknose C 6 25 Blacknose F C 6 25 Blacknose F C 6 25 Blacknose F C 6 25 Blacknose F C 6 25 Blacknose F C 6 25 Blaeknose F C 6 25 Blacknose M C 6 25 Blacknose M C 6 25 Blacknose F A 6 25 Blacknose F A 6 25 Blacknose M A 6 25 Blacknose M A 6 26 Blacknose F C 6 26 Blacknose F C 6 26 Blacknose F C 6 26 Blacknose F C 6 26 Blacknose F C 6 26 Blacknose F C 6 26 Blacknose F C 6 26 Blacknose F C 6 26 Blacknose F C 6 26 Blacknose F C 6 26 Blacknose M C 6 26 Blacknose M C 6 26 Blacknose M C 6 26 Blacknose M C 6 26 Blacknose M C 6 26 Blacknose M C 6 26 Blacknose M C 6 26 Blacknose M C 6 26 Blacknose M C 6 26 Blacknose F B 6 26 Blacknose F B 6 26 Blacknose M B 6 26 Blacknose M B 6 27 Blacknose F C 6 27 Blacknose F C 6 27 Blacknose F C 6 27 Blacknose F C 6 27 Blacknose F C 6 27 Blacknose F C 6 27 Blacknose F C 6 27 Blacknose F C 6 27 Blacknose F C 6 27 Blacknose F C 6 27 Blacknose M C 6 27 Blacknose M C 6 27 Blacknose M C 6 27 Blacknose M C 6 27 Blacknose M C 6 27 Blacknose M C 6 27 Blacknose M C 6 27 Blacknose M C 6 27 Blacknose M C 6 27 Blacknose M C 6 27 Blacknose A

8 MO DA COMMON NAME SEX REPRO. PC (em) FL (em) TL (em) STL (em) TAG # LOCATION 6 27 Blacknose A 6 27 Blacknose F A 6 27 Blacknose F A 6 27 Blacknose F A 6 27 Blaeknose F A 6 27 Blacknose F A 6 27 Blacknose F A 6 27 Blacknose F A 6 27 Blacknose F A 6 27 Blacknose F A 6 27 Blacknose M A 6 27 Blacknose M A 6 27 Blacknose M A 6 27 Blacknose M A 6 27 Blacknose M A 6 27 Blacknose M A 6 27 Blacknose M A 6 27 Blacknose M A 6 27 Blacknose M A 6 27 Blacknose M B 6 27 Blacknose M B 6 28 Blacknose C 6 28 Blacknose F C 6 28 Blacknose F C 6 28 Blacknose F C 6 28 Blacknose F C 6 28 Blacknose F C 6 28 Blacknose F C 6 28 Blacknose F C 6 28 Blacknose M C 6 28 Blacknose M C 6 28 Blacknose M C 6 28 Blacknose M C 6 28 Blacknose M C 6 28 Blacknose M C 6 28 Blacknose M C 6 28 Blacknose M C 6 28 Blacknose M C 6 28 Blacknose M C 6 28 Blacknose M C 6 28 Blacknose M C 6 28 Blacknose F A 6 28 Blacknose F A 6 28 Blacknose F A 6 28 Blacknose M A 6 28 Blacknose M A 6 28 Blacknose M A 6 28 Blacknose M A 6 28 Blacknose M A 6 29 Blacknose F C 6 29 Blacknose F C 6 29 Blacknose F C 6 29 Blacknose F C 6 29 Blacknose F C 6 29 Blacknose F C 6 29 Blacknose F C 6 29 Blacknose M C

9 MO DA COMMON NAME SEX REPRO. PC (em) FL (em) TL (em) STL (em) TAG # LOCATION 6 29 Blaeknose M C 6 29 Blaeknose M C 6 29 Blaeknose M C 6 29 Blaeknose M C 6 29 Blaeknose M C 6 29 Blaeknose M C 6 29 Blaeknose F A 6 29 Blaeknose F A 6 29 Blaeknose F A 6 29 Blaeknose F A 6 29 Blaeknose F A 6 29 Blaeknose F A 6 29 Blaeknose F A 6 29 Blaeknose M A 6 29 Blacknose M A 6 29 Blaeknose M A 6 30 Blacknose F C 6 30 Blacknose F C 6 30 Blacknose F C 6 30 Blacknose F C 6 30 Blacknose M C 6 30 Blacknose M C 6 30 Blacknose M C 6 30 Blacknose A 6 30 Blacknose F A 6 30 Blacknose F A 6 30 Blacknose F A 6 30 Blacknose F A 6 30 Blacknose F A 6 30 Blacknose M A 6 30 Blacknose M A 6 30 Blacknose M A 7 1 Blacknose F C 7 1 Blaeknose M C 7 1 Blaeknose M C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blaeknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blaeknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose F C 7 3 Blacknose M C 7 3 Blacknose M C

10 MO DA COMMON NAME SEX REPRO. PC (em) FL (em) TL (em) STL (em) TAG # LOCATION 7 3 Blacknose M C 7 3 Blacknose M C 7 3 Blacknose M C 7 3 Blacknose M C 7 3 Blacknose M C 7 3 Blacknose M C 7 3 Blacknose M C 7 3 Blacknose M C 7 3 Bfacknose M C 7 3 Blacknose M C 7 3 Bfacknose M C 7 3 Bfacknose M C 7 3 Bfacknose M C 7 3 Bfacknose M C 7 3 Bfacknose M C 6 26 Bfacktip F B 6 26 Bfacktip M B 6 26 Bfacktip F B 6 27 Blacktip F A 6 27 Bfackt ip M A 6 27 Bfacktip M A 6 27 Bfacktip F B 6 27 Bfacktip F B 6 27 Blacktip F B 6 27 Bfacktip M B 6 27 Bfacktip F B 6 27 Bfacktip M B 6 29 Bfacktip F A 6 30 Bfacktip M A 6 26 Bonnethead F B 6 26 Bonnethead F B 6 26 Bonnethead F B 6 26 Bonnethead M B 6 26 Bonnethead M B 6 26 Bonnethead M B 6 23 Buff M A 6 27 Sharpnose F A 6 25 Spinner M C 6 29 Spinner F C