Movement of gray snapper Lutjanus griseus among subtropical seagrass, mangrove, and coral reef habitats

Abstract

Many fishes are thought to make diel, seasonal and/or ontogenetic migrations among seagrass, mangrove, and coral reef habitats. However, most evidence of such movement has been inferred from density and size structure differences among these habitats in tropical waters. The aim of the present study was to directly evaluate multiple habitat use by an ecologically and economically important reef fish, the gray snapper Lutjanus griseus, in subtropical waters. An integrated set of activities was conducted, including tagging and tracking of individuals and underwater video photography to examine the spatial and temporal dynamics of movements among neighboring mangrove, seagrass, and coral reef habitats in the northern Florida Keys, USA. Results of ultrasonic acoustic and mini-archival tagging indicated that L. griseus exhibits: (1) a distinct diel migration pattern, whereby shallow seagrass beds are frequented nocturnally and mangroves and other habitats with complex structure are occupied diurnally, and (2) bay-to-ocean movement, occurring during the known spawning season of L. griseus in this region. Video photography confirmed diel movement among seagrass and mangrove habitats. Results of this subtropical study corroborate direct and indirect evidence obtained in tropical waters of multiple inshore habitat use by L. griseus, as well as its seasonal movement into or towards offshore reefs. For resource managers charged with designing and implementing management plans for subtropical coastal habitats and fisheries, our findings provide direct support for the strategy of conserving both inshore seagrass and mangrove habitats as well as offshore coral reefs.KEY WORDS: Diel · Seasonal · Gray snapper · Movement · Mangrove · Seagrass · Reef · Acoustic tagging · Underwater video Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 380: [255][256][257][258][259][260][261][262][263][264][265][266][267][268][269] 2009 structure (e.g. Cocheret de la Morinière et al. 2002, Nagelkerken 2007, dietary isotopes, and gut content analysis (Harrigan et al. 1989, Cocheret de la Morinière et al. 2003 or from otolith microchemistry (Chittaro et al. 2004). Recent work in Atlantic and Caribbean waters strongly suggests mangrove and seagrass 'back-reef' areas are a critical ontogenetic link in the life cycle of a number of coral reef fishes, serving as important nurseries for juveniles (e.g. Nagelkerken et al. 2000, Serafy et al. 2003, Mumby et al. 2004, Adams et al. 2006, Dorenbosch et al. 2007). Three recent reviews examining mangroves as fish habitat (Faunce & Serafy 2006, Nagelkerken 2007, Nagelkerken et al. 2008 have noted the dearth of direct evidence of fish movement among mangroves and other coastal habitats. Such species-specific data are needed to begin to quantify the contributions made by adjacent, shallow-water habitats in the life cycles and sustainability of managed fish species (Beck et al. 2001).Nearshore mangrove and seagrass habitats along the southern Florida (USA...

Grouper and snapper movements and habitat use in Dry Tortugas, Florida

“…58 and 59 corresponded to spawning movements; further research into the importance of the Tortugas NTMRs for spawning yellowtail snapper is recommended. Consistent with observations by Moe (1972) and Luo et al (2009), a tagged gray snapper made routine nocturnal migrations between site B19 (see Fig. 1C) and presumed foraging habitats west of the array, possibly outside the RNA.…”

Ecological connectivity and niche differentiation between two closely related fish species in the mangrove-seagrass-coral reef continuum

“…A tagging study by Kaunda-Arara & Rose (2004) showed that adult L. fulviflamma swam distances up to 2 km, confirming that this species is capable of migrating between coral reefs and seagrass beds. Feeding migrations from coral reefs to adjacent seagrass beds have been documented for other snappers in the Florida Keys, USA (Luo et al 2009), and in the US Virgin Islands (Hitt et al 2011). The lack of potential food items from Mafia coral reefs in our study, however, limit our results, and further studies, tagging and following large individuals on coral reefs, are needed to confirm feeding migrations between coral reefs and seagrass beds by L. fulviflamma.…”

Relative predation risk for fishes along a subtropical mangrove–seagrass ecotone

“…This is further supported by studies from Bahamian waters documenting that lemon sharks, one of the main predators identified in our study, tend to focus search efforts near the mangrove shoreline (Morrissey & Gruber 1993, Franks 2007. Recent acoustic tracking of gray snapper in Biscayne Bay (Luo et al 2009) also indicates that the snappers may avoid foraging near the mangroves at night. At sunset, gray snapper migrate rapidly out of the mangroves in a synchronized fashion and do not forage in seagrass nearest the mangroves, but rather move as much as 500 m offshore, before returning to the same mangrove proproots the following morning (Luo et al 2009).…”