Co-evolution of “race-to-fish” dynamics and declining size structures in an expanding commercial coral-reef fishery

Abstract

Spatial expansions can provide a false sense of sustainability to fish markets and their consumers who perceive stable landings through time despite localized depletions. This study examined attributes of monthly landings and changes in size structures within a commercial coral-reef fishery that had stable landings for 11 years. Regression models revealed a significant rise in the ratio of landings between calm and windy months, depicting that stable landings were driven by increased fishing effort or success during the calmer months when less exploited reefs became accessible. Within the calmer months, ''race-to-fish'' dynamics also evolved for some target species, such as parrotfishes, whose landings became increasingly concentrated towards the onset of calm favorable conditions. During this same time, the size structure for 15 out of 19 target species that comprised 60% of annual landings decreased. The cumulative results suggested that (1) spatial management units can be improved by taking environmental gradients that define fishing access into consideration, and (2) thresholds for size-and-agebased policies should be established with respect to life-history parameters that maximize cohort production and protect against declining size structures. Both recommendations resonate with traditional forms of management across the Pacific that were based on reef tenure and knowledge of how species respond to fishing pressure.

Evolutionary management of coral‐reef fisheries using phylogenies to predict density dependence

“…2018, Cuetos‐Bueno et al. 2019). Daily visits to prominent fish markets were conducted where fishers were interviewed, and each fish landed was photographed.…”

“…2018, Cuetos‐Bueno et al. 2019). We further isolated on target species that comprised 90% of the landings within each family that were captured by the night‐spear fishery, representing the dominant fishing method for all islands comprising over 75% of landings.…”

“…Fisheries-dependent data sets and fish fin clips were gathered from eight jurisdictions across Micronesia, tropical North Pacific: Guam, Commonwealth of the Northern Mariana Islands (Saipan and Tinian islands), Yap, Pohnpei, Chuuk, Kosrae, the Republic of Palau, and the Republic of the Marshall Islands (Majuro and Arno atolls). Fisheries-dependent data sets were derived from standardized, intensive sampling efforts across 1 yr for all islands except Guam (Houk et al 2012, Houk et al 2017, Houk et al 2018b, Rhodes et al 2018, Cuetos-Bueno et al 2019. Daily visits to prominent fish markets were conducted where fishers were interviewed, and each fish landed was photographed.…”

“…We examined the four most abundant fish families: snappers (lutjanids), emperorfishes (lethrinids), surgeonfishes (acanthurids), and parrotfishes (scarine-labrids) (Houk et al 2017, Houk et al 2018b, Rhodes et al 2018, Cuetos-Bueno et al 2019. We further isolated on target species that comprised 90% of the landings within each family that were captured by the night-spear fishery, representing the dominant fishing method for all islands comprising over 75% of landings.…”

Assessing the quantity and quality of marine protected areas in the Mariana Islands

“…The Exclusive Economic Zone (EEZ) extends from 12 to 200 nautical miles. These diverging paths toward governance present opportunities and challenges for ocean conservation and fisheries management within and across the two jurisdictions (Cuetos-Bueno et al, 2018;Houk et al, 2018).…”