15 - Nassau grouper research in Belize

Nassau grouper research in Belize

In January 2011, I visited Belize to work with Janet Gibson and the Wildlife Conservation Society and help evaluate the monitoring protocol used to count Nassau grouper, Epinephelus striatus,in their spawning aggregations. I visited the two biggest aggregations monitored regularly by Belize’s national Spawning Aggregation Working Group (SAWG); Northeast Pt, Glover’s Reef (1,800 fish in 2011) monitored by WCS and partners, and Lighthouse reef, Sandbore, with the University of Belize monitoring team (1,300 fish in 2011). The crosssector SAWG was established in 2001 following a nationwide survey of Nassau grouper which showed that many of their spawning aggregations had low fish numbers (hundreds to a few thousands) compared to historical highs of tens of thousands.The WG has played a pivotal role in the introduction of various legislation, including protection of all aggregation sites, a four-month closed season and a minimum capture size for Nassau grouper in Belize. It is a noteworthy model for collaboration and cooperation in aggregation management at the national level (www.spagbelize.org)

After the January field trip, my first experience diving in Belize’s beautiful waters, I attended a special meeting of the SAWG to present information on the management requirements of aggregating species and to discuss the sampling protocols being used.

The 21 participants at the meeting comprised staff of the Fisheries Department and the University of Belize, conservation NGOs, co-managers of marine reserves and a fisherman. SAWG members have been monitoring seven of the 11 known aggregation sites for Nassau grouper since 2003. In 2011 fish numbers continued to be low for most sites, with no Nassau groupers reported at two of the aggregation locations. Some of the low counts could be due to rough weather experienced in February, when many dives had to be cancelled. In addition, groupers may not spawn every season, which can result in smaller aggregations sometimes. The Nassau grouper is particularly challenging to count in aggregations because, just prior to spawning, the fish gather together from all over the aggregation site to rise up from the substrate and form large mobile spheres or ‘balls’ that move slowly away as divers approach. We are discussing different methods for counting fish numbers in these ‘balls’ and plan to trial them in January 2012.

Yvonne Sadovy de Mitcheson
SCRFA
This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Reference

BELIZE Information Circular No. 9, The Belize Spawning Aggregation Working Group. (2011). Glovers Reef Final SPAG Report 2005-2011.

Further information:

http://www.youtube.com/watch?v=JFbJsj8KdSI&feature=related