Conservation Evidence strives to be as useful to conservationists as possible. Please take our survey to help the team improve our resource.

Providing evidence to improve practice

Individual study: Benefits of a replenishment zone revealed through trends in focal species at Glover’s Atoll, Belize

Published source details

Tewfik A., Babcock E., Gibson J., Burns P.V. & Strindberg S. (2017) Benefits of a replenishment zone revealed through trends in focal species at Glover’s Atoll, Belize. Marine Ecology Progress Series, 580, 37-56

This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Designate a Marine Protected Area with a zonation system of activity restrictions Subtidal Benthic Invertebrate Conservation

A site comparison study in 2007–2013 of 11–23 coral reef sites inside Glover’s Reef Marine Reserve, Caribbean Sea, Belize (Tewfik et al. 2017) found that the effects of a protected no-take area on the abundances and sizes of queen conch Lobatus gigas and Caribbean spiny lobster Panulirus argus, compared to the protected general-use zone with only some restrictions, varied with the size of individuals., Inside the marine reserve, 14 to 20 years after its designation, abundance of mature conch (>5 mm lip thickness) increased over time in the no-take sites (from 4/ha in 2007 to 17/ha in 2013), and was greater than in the general-use sites where the change (from 1 to 2/ha) was not significant. Immature conch (<5 mm) abundance increased similarly in no-take (from 4 to 53/ha) and general-use sites (from <1 to 33/ha). The lip thickness of mature conch decreased similarly over time at all sites (from 11 to 9 mm). The shell length of immature conch decreased similarly over time in no-take sites (from 221 to 182 mm) and general-use sites (from 234 to 186 mm). Abundance of legal-size (>76 mm carapace length) and sub-legal (<76 mm) lobsters increased over time in the no-take sites (legal-size: from 6 to 16/ha; sub-legal: from 1 to 3/ha) but did not change in the general-use sites (legal-size: non-significant change from 6 to 5/ha; sub-legal: remained at 6/ha). The size of all lobsters decreased over time in both no-take sites (legal-size: from 120 to 110 mm; sub-legal: from 59 to 52 mm) and general-use sites (legal-size: from 110 to 100 mm; sub-legal: from 59 to 52 mm). Glover’s Reef Atoll was designated as a Marine Reserve in 1993 and included a no-take area (79.6 km2) and a general-use area with fishery restrictions (including: ban on the use of SCUBA to collect any seafood, closed seasons, and size limits for queen conch and spiny lobster). Once a year in April–June 2007–2013, conch and lobsters were surveyed at 1.6 m average depth inside the no-take area (6–18 sites/year) and inside the general-use zone (5 sites/year). At each site (0.04–1.43 ha), snorkelers counted and measured all conch (shell length; lip thickness) and lobster (carapace length).

(Summarised by Anaëlle Lemasson & Laura Pettit)