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PRESCOTT COLLEGE KINO BAY CENTER FOR CULTURAL AND ECOLOGICAL STUDIES SHRIMP TRAWLER BY-CATCH DIVERSITY AND IMPACT STUDIES , 2008-2015 SHRIMP TRAWLER BY-CATCH DIVERSITY AND IMPACTS STUDIES Background: The shrimp fishery is the most important fishery in Mexico in terms of value, exports, and employment. In 2008, the Mexican shrimp fishery landed 196,289 metric tons (MT) of shrimp. Sonora produces more shrimp than any other state in Mexico; producing 96,557 MT of shrimp in 2008, representing 49.2% of the national catch. Although the majority of shrimp produced in Mexico (66.3% of national shrimp production) now comes from aquaculture, trawling still represents a sizable economic force and has significant environmental and socioeconomic impacts. According to world averages compiled by the FAO, global shrimp trawling has an average rate of 84% by-catch, the highest by-catch percentage of any fishing industry, and produces one third of global fisheries discards. By-catch rates in the southern GOC have been documented between 83% and 97%, exemplifying that the percent of by-catch from the trawled shrimp fishery in the GOC is generally higher than the global average. The overcapitalization of the shrimp trawling fleet also causes economic impacts on small-scale fisheries, resulting from competition for the same resources, habitat disturbance, and the by-catch and discard of juveniles of important commercial species, as well as the retention and sale of marketable-sized individuals of commercial species. Information specifically about the by-catch associated with trawling in the GOC is needed to inform the development of sustainable fisheries management programs. Beginning in 1999 Prescott College students have participated in on-board shrimp trawler studies in the Kino Bay region. The study began as an educational experience for students in the Marine Conservation Biology classes. Over time we began to frame research questions relative to the economic development of the fishery and the economic and ecological impacts of by-catch mortality resulting from the fishery. In 2005 we published an article entitled “Export market influence on the development of the Pacific shrimp fishery of Sonora, Mexico”. Since 2003 we have sampled by-catch from 95 trawl sets on 11 boats over 23 nights, during, at minimum, the month of November of 2003, 2004, 2006, 2007, 2008, 2009, 2011, 2012, 2013, and 2014. As of 2014, a total of 221 species, including 130 species of fish from 58 families, 90 species of invertebrates from 14 phyla, and one sea turtle species have been documented throughout this study, and a 87.72 % rate of by-catch was calculated based on data from the all years combined. This study highlights the strong ecological and economic rationale for by-catch management within the shrimp fishery of the GOC. 1 PRESCOTT COLLEGE KINO BAY CENTER FOR CULTURAL AND ECOLOGICAL STUDIES SHRIMP TRAWLER BY-CATCH DIVERSITY AND IMPACT STUDIES , 2008-2015 Throughout the by-catch monitoring project, the presence of sensitive by-catch species has been observed. These species include the Pacific Seahorse (Hippocampus ingens), Totoaba (Totoaba macdonaldi), Loggerhead Turtle (Caretta caretta), Pacific Angel Shark (Squatina californica), Scalloped Hammerhead (Sphyrna lewini), Shovelnose Guitarfish (Rhinobatos productus), Oscillated Electric Ray (Diplobatis ommata), and Golden Cownose Ray (Rhinoptera steindachneri), all of which are listed on the IUCN Red List under varying degrees of severity from Critically Endangered to Near Threatened. Additionally there are several species common in the by-catch, which have commercial importance to the local panga fishers of Kino, whose populations in the GOC have rarely, if ever, been studied. These include the Bullseye Pufferfish (Sphoeroides annulatus), and the Finescale Triggerfish (Balistes polylepis), and nearly all of the 23 species of elasmobranchs documented throughout the by-catch monitoring project. Elasmobranchs are known to be particularly vulnerable to large-scale extraction, and it is also known that at least two elasmobranch species present in the by-catch have genetically distinct populations in the Gulf (the Shovelnose Guitarfish and the Pacific Angel Shark). Participants of the bycatch monitoring project have noted a marked increase in the retention of sensitive and commercially valuable species onboard the trawlers, as the practice of selling by-catch to local panga fishers has become more prevalent. This portion of the study aims to record the frequency of these species caught as by-catch as well as collect information about the size and maturity of every individual. 2008-2009 season report: We analyzed all of our by-catch data and summarized the results. Results from this study were used to submit comments to Mexican National Fisheries Institute (INAPESCA) for use in the revisions of the “Carta Nacional Pesquera”. We noted that several of the species frequently found as juveniles in the by-catch are both highly valued by commercial small-scale fishers in the region, and are also particularly sensitive to overexploitation due to their life histories. 2009-2010 season report: This year we revised the data collection protocols and added new research questions and methodologies to further study the impact of trawling on certain sensitive and/or commercially important by-catch species. Data from this year’s sampling indicated a by-catch rate of 86.5% by weight. As of this year a total of 181 species, including 114 species of fish from 55 families, 66 species of invertebrates from eight phyla, and one sea turtle species have been documented throughout the six years of this study. Over the course of the study, photographs have been taken of every species and compiled into a Power Point Catalog to be used for training and onboard reference by observer teams. In 2009, regional taxonomy experts reviewed the cumulative photo catalogue to ensure correct species identification. The results of this study were presented at this year’s XII Congreso de la Asociación del Mar de Cortés y VI Simposium Internacional Sobre el Mar de Cortés in Guaymas, Sonora, where we networked with academics and professionals in the fields of fisheries, population genetics, and elasmobranchs, encouraging outside researchers to come and assist with the project. In addition, these data will be used in an article to be submitted for publication. This year we added additional methodologies to collect data on the species of special concern. To quantify the incidence of juvenile, sensitive, and/or commercially important by-catch species, all individual elasmobranchs (excluding the Urobatids, which were far to numerous for the scope of this study and do not have commercial value), Finescale Triggerfish, Bullseye Pufferfish, and Pacific Seahorses that were present in the by-catch were measured, weighed and sexed (when possible) to obtain a measure of the landed biomass and size-frequency data. These particular species were chosen because of their consistent presence in the by-catch, the feasibility of collecting all individuals, and the 2 PRESCOTT COLLEGE KINO BAY CENTER FOR CULTURAL AND ECOLOGICAL STUDIES SHRIMP TRAWLER BY-CATCH DIVERSITY AND IMPACT STUDIES , 2008-2015 general lack of available data on regional populations. Other common and commercially important species, such as the Urobatids, flatfish, corvinas, and Blue-swimming Crabs (Calinectes spp.) were too numerous for the scale of this study. Data were collected from18 trawls on one trawler over four nights in November of 2009. Through literature reviews, we were able to determine that 99% of Finescale Triggerfish, 95% of Bullseye Pufferfish, and 80% of male and 78% of female Shovelnose Guitarfish recorded in our study were below the minimum known reproductive size. 2010-2011 Season Report: Due to the inability to receive permission from the Kino port captain to board trawlers in the region, field data for by-catch project was not collected this year. We have now begun to seek official collaboration and permitting for the project through Regional Fisheries Research Center of Guaymas (CRIP–Guaymas) and Mexican National Commission of Aquaculture and Fisheries (CONAPESCA). An article entitled “Management Implications of the Biodiversity and Socio-economic Impacts of Shrimp Trawler By-catch in Bahía de Kino, Sonora, México” was completed and submitted for publication to a peer-reviewed journal. 2011-2012 season report: This season we were able to monitor by-catch associated with seven trawls over two nights. Size, sex and sexual maturity data were collected for all species of elasmobranchs. Our work on this project through 2010 were published in a peer-reviewed on-line journal. Meltzer, L., Blinick, N.S. and A. B. Fleishman. 2012. Management Implications of the Biodiversity and Socio- Economic Impacts of Shrimp Trawler By-Catch in Bahía de Kino, Sonora, México. PLoS ONE 7(6): e35609. doi:10.1371/journal.pone.0035609 2012-2013 season report: This season we were able to monitor by-catch associated with eight trawls over two nights. Size, sex and sexual maturity data were collected for all species of elasmobranchs. Conversations with officials from CRIP-Guaymas about future directions and management implications of the project were initiated. 2013-2014 Season Report: This season we were able to monitor by-catch associated with 23 trawls over five nights in October and November and found an average of 88.84% by-catch. There were 11 previously unobserved species recorded including two elasmobranchs, the Pacific Sharpnose Shark (Rhizoprionodon longurio) and the Oscillated Electric Ray (Diplobatis ommata) which is listed as Vulnerable (IUCN). A pilot study was initiated to determine the current economic value of Paralichthys species which was found to total 5,550 pesos in present-day market value. Results were presented as a scientific poster entitled, “Ecological and Socio-economic impacts of by-catch mortality associated with shrimp trawling in Bahía de Kino, Sonora, México” at the Western Division of the American Fisheries Society conference. Additionally, a Café Comunitario was held in both Punta Chueca and Desemboque to share the project’s goals and results, and to open the door for future collaboration with interested community members. 2014-2015 season report: This season we were able to monitor bycatch associated with 25 trawls over six nights in October, November, and December of 2014, and February 2015.The calculated percentage of bycatch per trawl ranged from 74.01% to 98.43% with a season average of 89.36%; this rate rose throughout the season. The number of species recorded per trawl ranged from 53 to 73. In total, 174 species were recorded throughout the season including the following 25 previously unrecorded species (7 fishes and 18 invertebrates) (Table 20). 3 PRESCOTT COLLEGE KINO BAY CENTER FOR CULTURAL AND ECOLOGICAL STUDIES SHRIMP TRAWLER BY-CATCH DIVERSITY AND IMPACT STUDIES , 2008-2015 Table 1. Species recorded in shrimp trawler by-catch during 2014-2015 season. Blue indicates fish. Green indicates invertebrates . Scientific Name Common Name Date(s) Recorded Rhinobatos glaucostigma Speckled Guitarfish Oct. 14, 2014 Cephaloscyllium ventriosum Swellshark Feb. 6, 2015 Raja velezi Rasptail Skate Feb. 6, 2015 Brotula clarkae Pacific Bearded Brotula Feb. 6, 2015 Caranx vinctus Cocinero Cheilotrema saturnum Black Croaker Lobotes pacificus Pacific Tripletail Nov. 12, 2014 Demospongiae Red Sponge Dec. 10, 2014 Unknown Unknown Anemone Feb. 6, 2015 Unknown Unknown Annelid Worm Feb. 6, 2015 Arca pacifica Pacific Ark Shell Chione amathusia or californiensis Venus Clam Dosina (?) Unknown Tan Bivalve A Anadara sp. Cockle Shell Unknown Unknown Small Blue Unknown Slipper Snail Oliva porphyria Tent Olive Snail Feb. 6, 2015 Oliva polpasta Bulbous Olive Snail Feb. 6, 2015 Strombus gracilior Pacific Fighting Conch ALL Unknown Unknown Gastropod Nov. 12, 2014 Unknown Unknown Crab Ethusa ciliatifrons Giant Ciliate Ethusa Dec. 10, 2014; Feb. 6, 2015 Parapinnixa sp. Unknown Pea Crab Nov. 12, 2014 Pilumnus sp. Unknown Pilumnus Crab Nov. 12, 2014 Unknown Sea Cucumber Sp. C Nov. 19, 2014 Feb. 6, 2015 Nov. 12, 2015 Oct. 15 – Nov. 9, 2014 Nov. 9, 2014 Nov. 9/12, 2015 Nov. 9, 2014 Nov. 19, Dec. 10, 2014 Feb. 6, 2015 Nov. 9, 2014; Feb. 6, 2015 To further the study objective of collecting data on species of special concern, a new protocol for determining maturity in female elasmobranchs through dissection was implemented on a trial basis. In the past, we have assigned maturity to elasmobranchs by measuring total length in sharks or disc width in skates, then comparing those to published sizes at maturity for each species. Unfortunately, elasmobranchs are understudied in the GOC, meaning that for many species the maturity information is missing, or only exists from studies done in the Pacific Ocean. For these reasons, one of the added 4 PRESCOTT COLLEGE KINO BAY CENTER FOR CULTURAL AND ECOLOGICAL STUDIES SHRIMP TRAWLER BY-CATCH DIVERSITY AND IMPACT STUDIES , 2008-2015 objectives to this study was to clarify the maturity of individuals ourselves instead of relying on published sizes at maturity. For males, maturity was determined onboard through an assessment of the claspers. Individuals with fully calcified claspers that rotated 180 degrees and tips that opened easily when flexed were considered mature. Females were brought back to the station, frozen, and later dissected. Measurements included follicle diameter, shell gland width and weight, and ovary weight, with each measurement taken from both sides. These measurements were compared to published numbers when available and to the measurements of gravid individuals if there were no publications. We documented a previously unrecorded species into the Kino Bay- two individuals of the Speckled Guitarfish, Rhinobatos glaucostigma, were recorded in our study on October 14, which turned out to be the Northern-most record for this species in the GOC. Due to the extended field season, one of the most interesting things we were able to observe was how the species composition changes from October to February. This was an uncharacteristically warm year, resulting in the typical colder-water indicator species that we usually see in November, be recorded in February. These species include Paralichthys spp., Mustelid spp., Raja spp., and Sicyonia disedwardsi. We observed many individuals from several species over the season that were emaciated, melanistic, and potentially diseased. This could be a new phenomenon based on poor conditions and indicative of an unhealthy bay, or may have been overlooked previously in the study. These species include Sphoeroides annulatus (most individuals were significantly thin with small round lesions on their skin that resulted in the fishermen not retaining them for food on October 14), Orthoprisis reddingi (three individuals on two nights found to be melanistic and emaciated; comments from the crew indicate they had never seen them like this before), Cheilotrema saturnum (one individual-- newly recorded specieswith a very unusual body depth index). This was the first year we have observed the deaths of California Sea Lions in association with the shrimp fishery- they get caught in the propeller when there are large groups of them surrounding the boat. We are seeing decreased numbers of some species of special concern such as a complete three year absence of Hippocampus ingens which has previously been recorded every year from 2003-2011. An educational workshop was given in October 2014 to interested members of the Comcaac community and Prescott staff about the project's methodology and results. On January 28, a presentation was given to an audience of about 60 people at Club Deportivo, a sports fishing club in Kino Bay that focused on the project's results and consumer awareness. We began contributing data, specimens, and photographs to several international scientific databases, including the website Mexfish, the Marine Vertebrate Collection at SCRIPPS, and the Smithsonian Tropical Research Institute's Shorefishes of the Tropical Eastern Pacific online information system. We had the opportunity to participate in an informal fish-identification lab and discussion about the project at SCRIPPS to improve our identification techniques, broaden our collaborative network, and contribute unusual specimens to the collection. As of now, we have contributed photographs of 24 different fish species to Mexfish (www.mexfish.com) from the Kino Bay region and plan on continuing this effort in following years. The data from this study is being used in a project entitled '6&6'; a collaborative endeavor with Next Generation Sonoran Desert Researchers to artistically communicate scientific projects in the region. This project will be underway for at least the following year, and will likely result in a travelling exhibition through the United States and Mexico. 5 PRESCOTT COLLEGE KINO BAY CENTER FOR CULTURAL AND ECOLOGICAL STUDIES SHRIMP TRAWLER BY-CATCH DIVERSITY AND IMPACT STUDIES , 2008-2015 What we had previously identified as Bascanichthys cylindricus has been corrected to be Bascanichtys bascanoides based on our preserved specimen. Our data means a range extension as well as a maximum known length for this species. The unidentified Sea Catfish has been identified as Bagre panamensis; this may be two separate species. The unidentified Bonefish has been identified as Cortez Bonefish, Albula gilberti. What we had previously identified to be Cynoscion xanthulus, was corrected to be Cynoscion reticulates; we need to watch this group carefully to see if we do in fact see both species. 2015-2016 proposal: We plan to increase bycatch monitoring effort and would like to collaborate with regional elasmobranch experts to be able to analyze population impacts resulting from bycatch mortality. We also intend to continue consumer and public education about the impacts of shrimp trawling on ocean ecosystems and populations and upon small-scale fishing economies. 6