Marine biodiversity and animal behaviour

NEODAAS data have been used to compare locations of migrating animals with boundaries or contours of surface temperature or colour properties (e.g. Hays et al. 2006). SST data have also been used in a novel manner to fix latitude along the longitude on tracked basking sharks by comparison with tag recorded water temperature (Sims et al., 2005; 2006). Finally, Dixon et al. (2006) related surface phytoplankton concentration from SeaWiFS to spawning of an Atlantic vent mussel.

McMahon and Hays (2006) reported that Leatherback turtles appear to be limited in their distribution to areas warmer than 15 ºC in the north Atlantic. They then investigated the location of the 15 ºC contour from 17 years of SST data (provided by NEODAAS) and found a northward movement since 1983 (Fig. 1). This would have implications for Leatherback turtle distributions should warming of the Atlantic occur.

The position of the 15 ºC surface isotherm in different years

Figure 1: The position of the 15 ºC surface isotherm in different years. a) and b) AVHRR Satellite images comparing years when the position of this isotherm in August was at its most southerly extent (1985) and most northerly extent (2000). (c) The increasing northerly extent of the surface 15 ºC surface isotherm in August showing a northerly shift of 330 km (McMahon & Hays 2006).

Hays, G.C., Hobson, V.J., Metcalfe, J.D., Righton, D. & Sims, D.W. (2006) Flexible foraging movements of leatherback turtles across the north Atlantic Ocean. Ecology, 87(10), 2647-2656.

McMahon, C.R. & Hays, G.C. (2006) Thermal niche, large scale movements and implications of climate change for a critically endangered marine vertebrate. Global Change Biology, doi: 10.1111/j.1365-2486.2006.01174.x.

Dixon, D.R., Lowe, D.M., Miller, P.I., Villemin, G.R., Serrão-Santos, R. & Dixon, L.R.J. (2006) Evidence of seasonal reproduction in the Atlantic vent mussel Bathymodiolus azoricus, and an apparent link with the timing of photosynthetic primary production. Journal of Marine Biological Association, 86, 1363-1371.

Sims, D.W., Witt, M.J., Richardson, A.J., Southall, E.J. & Metcalfe, J.D. (2006) Encounter success of free-ranging marine predator movements across a dynamic prey landscape. Proceedings of the Royal Society B-Biological Sciences, 273(1591), 1195-1201.

Sims, D.W., E.J. Southall, G.A. Tarling, and J.D. Metcalfe, Habitat-specific normal and reverse diel vertical migration in the plankton-feeding basking shark, Journal of Animal Ecology, 74 (4), 755-761, 2005.