Journal of Fisheries and Life Sciences

Author(s): Kirsten Stokes, Kelly Scammon, Darian Double, Katie Toon, Shelli Hendricks, Aldo Alfonso Zavala Jimenez, Karla De La Pena and Katherine Comer Santos

Abstract: Illegal fishing activities are a worldwide threat affecting all ocean basins. At the Los Arcos Marine Reserve, located in Puerto Vallarta, Jalisco, Mexico management problems include overcrowding of tourist boats and illegal fishing activities. There is little enforcement of regulations due to lack of government personnel and resources. We took 30 systematic censuses of reef fish and recreational activities (boating and fishing) over two summer months in 2017 and 2018 to document species richness, fish densities, fish sizes, sea surface temperatures, and threats in the reserve. We identified 67 unique species during the study period, mostly small reef fish less than 81 cm total length. Species richness and densities were significantly higher in 2017 compared to 2018 (richness T=2.37; p=.040 and density T=2.16; p=.047). This could be related to significantly fewer boats and fishers in 2017 with buoys installed by a non-profit group to keep boats away from divers (T=-2.10; p=.045). In 2017, we found the expected significant negative trend between high recreational activity and low fish density (r²= -0.52; p=0.02) but in 2018 we found the opposite trend (r²=0.31; p=0.02). Removal of the buoys in 2018 apparently allowed SCUBA and snorkel tour operators to get closer to the Aquarium transect site and attract fish with bread bait. In general, Los Arcos species richness and densities are higher than other nearby areas and reserves. The team recommends education over enforcement to reduce illegal fishing activity and overcrowding of tour boats in this protected area in order to allow fish stocks to flourish, not only for their ecological roles, but also for the economic well-being of the local communities that depend on them for their livelihoods.