Now showing items 1-6 of 6

    • Conference paper

      Application of DNA-based markers in stock enhancement programs 

      MRR Romana-Eguia - In JH Primavera, ET Quinitio & MR Eguia (Eds.), Proceedings of the Regional Technical Consultation on Stock Enhancement for Threatened Species of International Concern, Iloilo City, Philippines, 13-15 July 2005, 2006 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Aquaculture and fisheries management require tools for identifying individuals or groups of aquatic organisms for the purpose of monitoring performance (growth, survival and behavior) and stock structure. In aquaculture research, commercially important traits of tagged individuals are assessed to generate supportive data for selective breeding, genetic improvement and commercial-scale fish farming. Fisheries management employs identification systems for the evaluation of stock abundance, population dynamics and documentation of wild and hatchery-bred stocks. Stock structure analysis is useful in the planning and implementation of sound stock management and more importantly, in stock enhancement programs. Blankenship and Leber (1995) underscored the inclusion of tagging/marking strategies for released hatchery stocks in the guidelines for responsible marine stock enhancement. Identifying and keeping track of introduced stocks in release habitats allows an assessment of their adaptability in the wild (Allendorf et al., 1988) and the success of the reseeding and/or restocking effort. Although often used interchangeably, the terms ‘tags’ and ‘markers’ differ by definition. Tags are artificial or synthetic materials that are attached to the aquatic organism to allow individual or group identification while markers are traits or characters either applied or inherent to the organism (Thorsteinsson, 2002). Tags/markers are essential in evaluating resource distribution patterns, behavior, migration and movement of stocks, dynamics of exploited aquatic populations and evolutionary processes, all of which comprise baseline information for any stock management, enhancement and conservation program in aquaculture and fisheries (Allendorf et al 1988, Mulvey et al., 1998).
    • Book

      Philippine Aquatic Wildlife Rescue and Response Manual Series: Marine Turtles 

      This manual addresses the lack of information materials on how to deal with marine turtle encounters in the Philippine seas to ensure that the proper treatment and intervention is provided. The manual also responds to the Comprehensive Action Plan for Threatened, Charismatic, and Migratory Species of the Sulu-Sulawesi Marine Ecoregion (SSME), which has been identified as the first priority seascape the Coral Triangle Initiative (CTI). The Tri-National Committee of the SSME developed the Comprehensive Action Plans (CAP) that identified seven Key Result Areas (KRAs) to improve the status of marine turtles in the SSME, as follows: (a) Identify best practices in minimizing threats to marine turtle populations and their habitats; (b) Develop and implement nesting habitats and management programs to maximize hatchling production and survival; (c) Provide recommendations on specific features or criteria in marine protected area (MPA) design and MPA network design in relation to the protection and management of marine turtles in SSME waters; (d) Undertake initiatives to promote reduction of incidental capture and mortality of marine turtles; (e) Conduct turtle population habitat research and monitoring protocols; (f) Develop guidelines for MPA network design for marine turtles; and (g) Publish information to promote best practices and successes for marine turtle conservation.

      This manual is an important step to address gaps and issues on threatened marine wildlife in the Philippines to better protect and conserve marine biodiversity in the Coral Triangle.
    • Article

      The sea turtles captured by coastal fisheries in the northeastern Sulu Sea, Philippines: Documentation, care, and release 

      TU Bagarinao - Herpetological Conservation and Biology, 2011 - Herpetological Conservation and Biology
      This paper presents the first substantive data on sea turtles in the northeastern Sulu Sea. Working with fishers and government, the Southeast Asian Fisheries Development Center (SEAFDEC FishWorld) documented 109 juvenile and adult sea turtles captured or stranded around Panay and Guimaras Islands, Philippines from 2001 to mid- 2011. These included 65 Green Turtles (Chelonia mydas), 15 Hawksbill Turtles (Eretmochelys imbricata), 24 Olive Ridley Turtles (Lepidochelys olivacea), three Leatherback Turtles (Dermochelys coriacea), and two Loggerhead Turtles (Caretta caretta). From the four fishing villages within 1 km of FishWorld came 29 Green Turtles, eight Olive Ridleys, and one specimen each of the three other species. Approximately 77% of the Green Turtles were caught in nearshore fish corrals, mostly between October and May; whereas, 75% of the Olive Ridley Turtles were caught in offshore gill nets and long lines between April and October. Seventy-nine captured turtles were released, 73 of them with inconel flipper tags. Several turtles died from entanglement, serious injuries, slaughter for market, or diseases. An Olive Ridley Turtle and three Green Turtles were seen nesting at three beaches in southern and western Panay. Nesting of Hawksbill Turtles has been recorded at secluded beaches in Lawi, Guimaras about every three years; several batches of hatchlings have been raised by local residents before being released. Size-specific growth rates of Green Turtles and Hawksbill Turtles were highest among post-hatchlings and decreased sharply with size among juveniles and adults.
    • Article

      A simple method of tagging prawns 

      LM Rodriguez - SEAFDEC Aquaculture Department Quarterly Research Report, 1977 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The recognition of individual animals is crucial to many aspects of research. Prawns (Penaeus monodon) present unique difficulties in this respect since they molt regularly. Thus, almost all tagging and marking methods developed for prawns so far have proven inadequate. Some tags or marks are lost during molting; others cause injury to the prawns. A new and efficient method has been developed at the Igang Seafarming Station of the Aquaculture Department.

      Rectangular brass tags measuring 5 mm by 20 mm and numbered consecutively are used. The prawn is held gently but firmly at the base of the carapace with the left hand while the right hand slips the brass tag around the stalk of the unablated eye and presses the tag gently. All tagging must be made under water to avoid stress.

      From May 29 to September 7 to a total of 348 unilaterally-ablated adult female prawns were tagged on the unablated eyestalk in 5 batches to enable individual observations on gonadal maturation, molting, and growth. Periodic examinations were made four times a month to coincide with the different phases of the lunar cycle. On each examination, survival and recovery rates were recorded. The data included death due to immediate mortality during ablation and loss to cannibalism for the duration of the experiments.

      In all five tagging experiments, most of the prawns recovered had their tags intact. These included even dead and molting animals.

      The eyestalk tagging method is suitable for prawns because the tags can be attached without causing injury and has no effect on the rate of growth, maturity, molting and behavior of the animal. The tags are identifiable and permanent; they remain attached to the animal even after death.
    • Article

      A simple method of tagging prawns 

      LM Rodriguez - Natural and Applied Science Bulletin, 1976 - University of the Philippines
      The recognition of individual animals is crucial to many aspects of research. Prawns present unique difficulties in this respect since they molt regularly. Thus almost all tagging and marking methods developed for prawns so far have proven inadequate. Some are lost during molting; others cause injury to the prawns. A new and efficient method has been developed at the Igang Sea Farming Station of the Aquaculture Department.

      Brass tags measuring 5 mm by 20 mm and numbered consecutively are encircled around the eyestalk like a small bracelet. The prawn is gently held at the base of the carapace by the left hand while the right hand slips the brass tag over the eye. The tag is gently pressed around the eyestalk to prevent its slipping out. All tagging is done under water to avoid stress.
    • Article

      The use of a Visual Implant tag to monitor the reproductive performance of individual milkfish Chanos chanos Forsskal 

      AC Emata & CL Marte - Journal of Applied Ichthyology, 1992 - Blackwell Publishing
      Nine-year old milkfish (3.8 kg., average body weight) were individually marked with Visible Implant (VI) tags to monitor their reproductive performance following hormonal induction. All tags were retained after one year; only 5 out of 64 tags were not readable due to improper implantation. The advantages of using VI tags include: less tagging time (less than one minute), high retention rate, longer retention, infection-free, and easily readable.