Integrating literature, industry participant knowledge, and fishery data to formulate management recommendations for a targeted marine aquarium species, Centropyge potteri (Pomacanthidae), in the Hawaiian Islands

As a result of growth in the global market for ornamental fishes over recent decades, an extensive commercial marine aquarium industry developed throughout the most populated Hawaiian Islands. To date, there are no monitoring programs established on O'ahu to gather continual data on reef fish abundance.;Centropyge potteri ranks as the 5th most collected marine aquarium fish in the state and is the most commonly collected marine aquarium fish collected on O'ahu. It is an endemic species. A documented decline of C. potteri abundance in West Hawai'i and lack of abundance data for the species on O'ahu where it is most targeted by aquarium fishers made it a prime candidate for study. Although a considerable amount of information is available on general ecology and reproduction of this reef fish, it is currently unclear whether exploitation, ecological disturbance, natural cycles of recruitment, or other unidentified causes affect its abundance. As with many reef fishes in Hawai'i, significant gaps in knowledge exist for C. potteri that may impede efforts to develop a sustainable wild-stock management strategy.;A multifaceted project conducted in 2006-2007 accessed a range of information about the Centropyge potteri fishery in the Hawaiian Islands. The principal goals of the project were to combine information from a variety of sources to provide an informational basis for management of this species and to formulate species-specific management recommendations based on the findings. Information was gathered thorough literature review, analysis of existing fishery data from the Department of Land and Natural Resources, and employment of standardized surveys for aquarium fish collectors on O'ahu and Hawai'i Island as well as guided, informal interviews with closely affiliated aquarium industry participants. Emphasis was placed on interviewing fishers since (1) they must gain extensive knowledge of fish ecology, biology, and physiology in order to provide delicate species to the industry without injury to the fish, and (2) it is critical to involve fishers and other industry participants in research since their increased involvement may improve creditability of collected data and enhance support for regulations based upon these data. This thesis project is the first known study to gather information from multiple marine aquarium industry participants to provide a basis for management of a targeted species in Hawai'i.;Data from fisher interviews indicated that juvenile C. potteri, recognizable when around 25 mm in total length (TL), settle in coral rubble, coral rich areas, and outer drop-off areas between June and September. Individuals between 50 and 80 mm, suggested by 2 interviewed fishers to be between 1 and 2 years of age, are captured at depths of 18 to 30 m using barrier-net fishing methods outlined in existing literature. Captured C. potteri must be raised to the surface slowly to avoid injury from overexpansion of the air bladder. Some fishers reported puncturing the air bladder with a syringe rather than allowing for sufficient decompression time. Centropyge potteri is otherwise transported, handled, packaged, and shipped using standard methods for most other Hawaiian aquarium species.;Monitoring data recorded in West Hawai'i between 1999 and 2006 indicated an overall decline in abundance of C. potteri in sites open to fishing, yet figures were not considered significant. Most West Hawai'i fishers reported uniform abundance among collection sites and observed no changes in abundance in recent years. On O'ahu, where fishing effort for C. potteri is most concentrated, fishers suggested varied abundance between collection sites, though these claims could not be quantitatively substantiated due to lack of continuous monitoring data. Whether collection pressure adversely affects populations of C. potteri over time remains unclear. Capture of this species appears largely demand driven and there has been a decline in demand for this species in recent years.;In conclusion, this thesis study, using C. potteri as a model, highlighted the importance of data collection in the management of marine ornamental fishes harvested from Hawai'i's reefs. This study further acknowledged informational gaps that remain for C. potteri, ongoing efforts to collect fishery and abundance data for the species and outlined the need for additional monitoring efforts on O'ahu. Results showed that social sampling of marine aquarium fishers and associated industry participants was an effective method for collecting useful information that can be applied to management of a targeted marine aquarium species. Based on overall study findings, two management tools that could potentially be useful for this fishery in the case of C. potteri are (1) limitations on fishing area, and (2) restrictions on the size of C. potteri collected. Neither, however, can be strongly recommended without more data on catch and abundance. (Abstract shortened by UMI.)...