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Providing evidence to improve practice

Individual study: Dramatic declines in red abalone populations after opening a “de facto” marine reserve to fishing: Testing temporal reserves

Published source details

Rogers-Bennett L., Hubbard K.E. & Juhasz C.I. (2013) Dramatic declines in red abalone populations after opening a “de facto” marine reserve to fishing: Testing temporal reserves. Biological Conservation, 157, 423-431


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

Establish temporary fisheries closures Subtidal Benthic Invertebrate Conservation

A replicated, before-and after study in 2004–2010 in a rocky seabed area in the North Pacific Ocean, northern California, USA (Rogers-Bennett et al. 2013) found that temporarily reopening an area previously closed to fishing led to a decline in abundance and size of red abalone Haliotis rufescens after three years. Abundance of abalone declined by 65% and was lower three years after reopening (0.45 abalone/m2) compared to during closure (1.3 abalone/m2). This was also true for the size of abalone (after reopening: 168 mm; during closure: 172 mm). Five months after closing the fisheries again, the abundance and size of abalone decreased further (abundance: 0.33/m2; size: 166 mm). In July 2004, an area where abalone fishing had been prohibited was reopened to fishing. In May 2010, the area was designated as a marine protected area and closed again to fishing. Red abalone abundance and size were recorded along a total of 83 transects (60 m2) in spring 2004 (prior to reopening fishing – 23 transects), September 2007 (during fishing – 33 transects), and September 2010 (five months after closing fishing again– 27 transects).

(Summarised by Anaëlle Lemasson)