Efficacy of harvest and minimum size limit regulations for controlling short‐term harvest in recreational fisheries

Abstract

It is important to consider the potential effectiveness of regulations for reducing total harvest levels when developing fishery management plans. A random forest (RF) modelling approach was used to examine how changing per‐angler harvest or minimum size limit regulations affected sport fishery harvest in US Atlantic coast recreational fisheries. Harvest limits per angler (i.e. bag limits) were typically high initially and subsequently reduced, whereas almost half of minimum length limits were initially below the length‐at‐maturity and subsequently increased. Across most fisheries examined, extreme reductions in harvest limits (e.g. from unlimited to catch‐and‐release) were largely ineffective at limiting total fishery harvest. Increasingly restrictive minimum length limits caused a greater average harvest reduction than per‐angler harvest limits. Some regulation changes were associated with higher angling effort and thus increased harvest, which suggests that when effort cannot be constrained, more direct harvest limitations should be considered.

Collaborative assessment of recreational fishing in a subtropical estuarine system: a case study with fishing guides from south‐eastern Brazil

“…The low proportion of anglers who reached the official harvest limits (15 kg plus one fish) reflects the ineffectiveness of this regulation when the initial quota is large and/or is implemented in areas where fishing effort is still unrestricted (Van Poorten et al . ). According to Van Poorten et al .…”

Towards resilient recreational fisheries on a global scale through improved understanding of fish and fisher behaviour

“…Post's (2013) opinion, 10 years after publishing the highly cited 'invisible collapse' article (Post et al 2002), was that many agencies and anglers still did not believe that angling mortality could drive fish populations to collapse, defined as population size reductions to <10% of virgin biomass. Van Poorten et al (2013) analysed the harvest-reduction effect of marine recreational fisheries regulations in the USA, and similarly noted that restrictive minimum-size limits would be needed to reduce harvest notably, while other harvest restrictions (e.g. Allen et al (2013) supported this conclusion by showing that unresponsive fishing effort, which essentially mimicked a situation where angler satisfaction was not only determined by catch rate or size of fish but also be non-catch factors such as travel distance, required reasonably high minimum-size limits or other harvest constraints to avoid recruitment overfishing.…”

“…Models, however, have shown that such sharp declines are indeed conceivable, even at realistically low levels of fishing effort (Hunt et al 2011). daily bag limits) were ineffective Van Poorten et al 2013). Van Poorten et al (2013) analysed the harvest-reduction effect of marine recreational fisheries regulations in the USA, and similarly noted that restrictive minimum-size limits would be needed to reduce harvest notably, while other harvest restrictions (e.g.…”

Long‐term trends in the catch characteristics of rainbow troutOncorhynchus mykiss, in a self‐sustained recreational fishery, Tongariro River, New Zealand

“…; Radomski ; van Poorten et al . ). Fishery management rules are applied equally to both skilled and unskilled anglers, but contribute to catch inequality because of the greater innate efficiency that skilled anglers have and because very few anglers catch their bag limit (Baccante ; Cook et al .…”

“…It has been proposed that inequality in catch distribution can be explained by chance (Thompson ; Alvarez & Schmidt ; Seekel ), the type of fishing tackle used (Baccante ), fisheries management actions (Baccante ; van Poorten et al . ) and fish abundance (Bannerot & Austin ). However, fish abundance is not easy to measure, so catch‐per‐unit‐effort (CPUE) – which is assumed to be proportional to population size (Quinn & Deriso ) – has often been used to explore inequalities in catch distribution.…”