Anthropause shows differential influence of tourism and a no‐take reserve on the abundance and size of two fished species

Abstract

Marine reserves are essential spatial conservation tools that have been shown to work alongside fishery management strategies to provide benefits to ecosystems and communities. Reserves often incentivize local tourism, which can provide the impetus for reserve creation but may have negative impacts on the ecosystem. The COVID‐19 pandemic paused global travel and provided an unprecedented opportunity to compare short‐term changes in exploited populations, during the reprieve from visitation provided by this ‘anthropause’, with the results of long‐term conservation management. Repeated surveys of Caribbean spiny lobster and Nassau grouper were conducted at popular dive and snorkel locations within a Bahamian no‐take reserve and surrounding areas during peak visitation prior to travel restrictions and immediately after restrictions were lifted. Repeated survey results were referenced against surveys over a broader area, including another Bahamian Bank, to examine the consistency of effects and how the ease of access for fishers impacted abundance. In the reserve, lobsters were encountered in significantly greater abundances, and significantly greater sizes of both lobster and grouper were observed in repeated surveys. Significantly more grouper were encountered during the repeated survey within the reserve after travel restrictions, but lobster abundances did not change significantly. Over a broader scale, lobster abundance was significantly greater further from population centres. Observed lobster abundance was affected by habitat and inferred fishing pressure, whereas observed grouper abundance was affected by survey depth, effort, and habitat. Marine reserves had clear benefits for both species and likely facilitated an increase in grouper abundance during the anthropause. Lobsters are a sustainably managed stock in The Bahamas, whereas grouper are a threatened species that appear to have benefited from an unplanned fishery restriction. Well‐managed marine reserves enhance populations long term and can have additive effects with fisheries management over short timescales.

Empirical support of predicted larval connectivity patterns demand conservation action for queen conch (Aliger gigas) in The Bahamas

“…Here, biophysical modeling results of larval transport from breeding within the ECLSP were significantly associated with the relative abundance of juvenile conch observed on dive surveys across a nearly 200 km span of islands and potential nursery habitat. Additionally, the abundance of adult conch on dive surveys was significantly associated with being within the ECLSP and the lip thickness of adults and the size of juveniles were significantly larger in the ECLSP than unprotected areas, reinforcing that the ECLSP is an effective refuge from harvest for conch (Kough et al, 2017; Stoner et al, 2012) as it is for other fished species (Kough et al, 2022; Mumby et al, 2007). This empirical support for an effective, well‐enforced marine reserve and for using biophysical larval transport modeling as a spatial planning tool should be strongly considered in conch conservation and management.…”

“…Fishers maximize yield by minimizing travel and targeting larger animals. In The Bahamas, proximity to dense human populations and greater fishing pressure decrease the abundance of conch (Stoner et al, 2018) and Caribbean spiny lobster (Kough et al, 2022). Adult and juvenile conch in the northern portion of the survey had on average the shortest shell lengths and thinnest lip thicknesses observed in the Exumas, suggesting that harvest is shaping the demographics of the area and leaving behind small, young animals.…”

Piscine predation rates vary relative to habitat, but not protected status, in an island chain with an established marine reserve

“…The 442 km 2 ECLSP was established as a no-take reserve in 1986, making it one of the oldest and largest MPAs in the Caribbean (Chiappone and Sullivan-Sealey, 2000). Prolonged exclusion from fishing pressure within the park has resulted in a higher biomass of predatory fishes, compared with other areas, for decades (Kough et al, 2022;Chiappone and Sullivan-Sealey, 2000;Mumby et al, 2007). The ECLSP is centrally located in the Exuma Cays, an island chain containing more than 365 islands and stretching for nearly 200 km in the central Bahamas.…”

“…were responsible for 28% of all recorded bites and a school of Thalassoma bifasciatum attacked a series of three Squidpops 109 times within a 75-minute recording. It is unlikely that the larger-sized fish in the area that are prized by fishers and benefit from MPA protections and harvest restrictions (Kough et al, 2022), such as grouper (Epinephelinae spp. ), would be directly…”