Projecting Range Limits with Coupled Thermal Tolerance - Climate Change Models: An Example Based on Gray Snapper (Lutjanus griseus) along the U.S. East Coast

Abstract

We couple a species range limit hypothesis with the output of an ensemble of general circulation models to project the poleward range limit of gray snapper. Using laboratory-derived thermal limits and statistical downscaling from IPCC AR4 general circulation models, we project that gray snapper will shift northwards; the magnitude of this shift is dependent on the magnitude of climate change. We also evaluate the uncertainty in our projection and find that statistical uncertainty associated with the experimentally-derived thermal limits is the largest contributor (∼ 65%) to overall quantified uncertainty. This finding argues for more experimental work aimed at understanding and parameterizing the effects of climate change and variability on marine species.

Native fish community structure and Indo-Pacific lionfish Pterois volitans densities along a depth-temperature gradient in Onslow Bay, North Carolina, USA

“…Range ex pansions of tropical and subtropical species north of Cape Hatteras are also expected (Hare et al 2012b), similar to poleward expansions predicted off the eastern coast of Australia (Figueira et al 2009, Figueira & Booth 2010. However, it is difficult to predict specific winners and losers with continued war ming, but given the high abundance of lionfish and their invasion success within the Atlantic, lionfish are likely to be one of the species to expand their range if winter temperatures become more physiologically hospitable (Sorte et al 2010a,b).…”

“…habitats < 27 m depth off North Carolina), then this could indicate that the thermal regime is shifting to favor more tropical species in general. Predicting future range expansions or contractions of other species is more problematic, since thermal tolerance data are not available for most species (but see Figue ira & Booth 2010, Hare et al 2012b). However, our analyses revealed several tropical species (in addition to lionfish) that are abundant yet restricted to warmer offshore depths in Onslow Bay but have wide depth distributions within the tropics (Tables 1, 2 & 3).…”

“…However, our analyses revealed several tropical species (in addition to lionfish) that are abundant yet restricted to warmer offshore depths in Onslow Bay but have wide depth distributions within the tropics (Tables 1, 2 & 3). We propose that these fishes (Halichoeres garnoti, Thalassoma bifasciatum, Holacanthus tricolor, Chro mis enchrysurus, C. scotti and C. insolatus) (Tables 1 & 2) may be good candidates as species most likely to expand their distributions shoreward and/ or northward (Hare et al 2012b) under current global warming scenarios (IPCC 2007). Collectively, this group of species could be considered an ecological indicator if (like lionfish) they become established year-round in areas previously uninhabitable (Table 3).…”

“…In addition, the temperature thresholds calculated in this study can now be used to project future fish community distributions based on various carbon emissions projections (Figs. 6 & 7) (Cheung et al 2012, Hare et al 2012b, Wuenschel et al 2012.…”

“…Fish communities in transition zones off the western coast of Australia and in the northern Gulf of Mexico and the Mediterranean Sea are becoming more tropical (Ben Rais Lasram & Mouillot 2009, Fodrie et al 2010, Wernberg et al 2013. Projections off the eastern coast of Australia and the United States are for warmer winter temperatures to increase overwintering survival of tropical fishes, resulting in range expansions (Figueira & Booth 2010, Hare et al 2012b). Thus, marine boundaries that represent zoogeographic transitions (e.g.…”