docFish Aggregations in the Florida Keys
download 
Report Transcription
Fish Aggregations in the Florida Keys
Fish Aggregations in the Florida Keys Observations of Mutton Snapper on Riley’s Hump Date and Station Numbers observed Moon phase 28 May−1 June 1999 1 fish in 3 of the 11 dives Full moon May 30* 31 July−3 Aug 2000 1 fish in 5 of the 6 dives New moon July 30* 17 July 2001 Station 2 10 3 days before new moon* 27 May 2002 Station 2 75 -100 1 day after full moon* 15 June 2003 Station 2 75 -100 1 day after full moon* 15 June 2003 Station 12 200 + 1 day after full moon* 4 July 2004 Station 12 300 2 days after full moon* 3 July 2007 Station 12 100 + 3 days after full moon** 12 June 2009 (1415-1715 hrs) ~4000 5 days after full moon*** •From: Burton ML, Brennan KJ, Muñoz RC, Parker RO Jr (2005) Preliminary evidence of increased spawning aggregations of mutton snapper (Lutjanus analis) at Riley’s Hump two years after establishment of the Tortugas South Ecological Reserve. Fish Bull 103:404–410. ** Mike Burton’s Trip report *** FWC current study TNER RNA TSER Mutton Snapper Spawning at Riley’s Hump TNER RNA TSER Changes in Abundance and Size-structure of Mutton Snapper 2000 Tortugas North Ecological Reserve Dry Tortugas National Park Future RNA Tortugas Bank --Open-Use Area Changes in Abundance and Size-structure of Mutton Snapper 2008 Tortugas North Ecological Reserve Dry Tortugas National Park RNA Tortugas Bank -- Open-Use Area Tagging of Mutton Snapper Regional connectivity of fishes within the Tortugas region of Florida – Riley’s Hump is a well known mutton snapper spawning aggregation site – Mutton snapper were acoustically tagged within the RNA & Riley’s Hump and tracked with a network of underwater ‘listening outposts’ • Listening Posts Tagging of Mutton Snapper • 55 Mutton snapper were tagged • 21 fish made multiple migratory trips to Riley’s Hump • 12 fish were residents of the RNA May 83° 05’ 83° 00’ 82° 55’ 24° 30’ 24° 35’ 24° 40’ TNER TSER July June 82° 50’ RNA DRTO Temperature (⁰C) Daily detection frequency Activity of Mutton Snapper at Riley’s Hump Date Utilization of Riley’s Hump Black and Scamp Grouper Cubera Snapper Mutton Snapper Multispecies Aggregation Site: Muttons and Triggers Multispecies Aggregation Site: Grouper Multispecies Aggregation Site: Cubera Snapper Fish Aggregations, Multi-species and Predictable Species D J F M A M J J A S O N Source Black grouper Domeier and Colin 1997, Eklund et al. 2000 Nassau grouper Domeier and Colin 1997, Fine 1990, Claro et al 2009 Scamp Domeier and Colin 1997 Nassau grouper Domeier and Colin 1997, Fine 1990, Claro et al 2009 Gag grouper Domeier and Colin 1997, Hood and Schlieder 1992 Red hind Domeier and Colin 1997, Beets and Friedlander 1998, Poholek, pers. com. Goliath grouper Domeier and Colin 1997, Sadovy and Eklund 1999, NMFS 2006 Yellowtail snapper Lindeman et al. 2000, Claro et al 2009 Dog snapper Lindeman et al. 2000, RNA report Mutton snapper Domeier and Colin 1997, Lindeman et al. 2000, Claro et al 2009, FWC observations, RNA report Gray snapper Domeier and Colin 1997, Lindeman et al. 2000, Claro et al 2009 Schoolmaster Lindeman et al. 2000 Lane snapper Lindeman et al. 2000, Claro et al 2009, Poholek pers. com. Cubera snapper Domeier and Colin 1997, Lindeman et al. 2000, Heyman et al 2005, Claro et al 2009, FWC observations, RNA report Permit Ault et al 2006, RNA report Larval Transport in February Larval Transport in July Reef Fish Aggregations in the Keys Reef Fish Aggregations in the Keys In the Upper Keys: Site Name Species Observed Whistle Buoy Cubera Snapper Carysfort Black Grouper Watson Reef* Mutton Snapper Description Several visual observations of 15-34 schooling cubera snapper (60-85 cm), June and July 2009 Several observations of 6-11 large black grouper (50-85 cm), Feb & March 2010 Visual observation of 35-45 mutton snapper (60-65 cm) swimming in water column Reef Fish Aggregations in the Keys Site Name Species Observed Description Western Dry Rocks Mutton snapper, gray snapper, yellow goatfish, mahogany snapper, spadefish, striped grunts Mangrove Toppino Gray snapper Eyeglass Bar Gray snapper, mutton snapper Maryland Shoal Gray snapper, yellowtail snapper Dozens of mutton snapper observed by divers May 2011, observations of 38 fishing boats on site in May 2011; Hundreds to over 1000 gray snapper observed over several months (June, July, and/or August) 2010 and 2012, with additional species Over 1000 gray snapper swimming in tight school over two successive days, August 2012 Hundreds of gray snapper observed over three consecutive months (June, July, August) 2010: Fishing boats observed catching mutton snapper in May 2012, no visual observation by divers Numerous schools of 12-25 fish, large (30-50 cm) fish, swimming in close formation. Observations of 10 fishing boats (1 commercial, 9 recreational) fishing on gray snapper in July 2010 Bathemetry of Reported Aggregation Site 30m Outlier Reef 30m Ridge 36m Ridge 50m Outlier Reef 30m Outlier Reef 30 and 36 m Ridges 50m Outlier Reef Aggregation Site Bathemetry of Known Aggregation Site Aggregation Site Bathemetry of Known Aggregation Site Western Dry Rocks Grey Snapper aggregation Local high relief Steep slope Outlier reef Aggregation site Grey Snapper at Mangrove Toppino Gray snapper aggregation Closing Remarks: In Florida: – No take marine reserves in Dry Tortugas have allowed for recovery of fish spawning aggregations – Larvae produced there supply recruits to the rest of Florida and the SE – Fish aggregations have been observed at several sites in the Florida Keys – Although spawning has not been observed at these sites, we have learned today that: IF YOU BUILD IT THEY WILL COME Any Questions?