[OANNES Foro] Tracking apex marine predator movements in the California Current marine ecosystem

Mie Jul 6 11:38:23 PDT 2011

Nature 
Volume: 475, Pages: 86-90 
(07 July 2011) 
doi:10.1038/nature10082 

Tracking apex marine predator movements in a dynamic ocean
B. A. Block,1 I. D. Jonsen,2 S. J. Jorgensen,1 A. J. Winship,2 S. A. Shaffer,3 S. J. Bograd,4 E. L. Hazen,4 D. G. Foley,4 G. A. Breed,2, 5 A.-L. Harrison,5 J. E. Ganong,1 A. Swithenbank,1 M. Castleton,1 H. Dewar,6 B. R. Mate,7 G. L. Shillinger,1 K. M. Schaefer,8 S. R. Benson,9 M. J. Weise,5 R. W. Henry5 & D. P. Costa5 
Stanford University, Biology Department, Hopkins Marine Station, Pacific Grove, California 93950, USA
B. A. Block, S. J. Jorgensen, J. E. Ganong, A. Swithenbank, M. Castleton & G. L. Shillinger 
Dalhousie University, Department of Biology, Halifax, Nova Scotia B3H 4J1, Canada
I. D. Jonsen, A. J. Winship & G. A. Breed 
San Jose State University, Department of Biological Sciences, San Jose, California 95192, USA
S. A. Shaffer 
NOAA Southwest Fisheries Science Center, Environmental Research Division, Pacific Grove, California 93950, USA
S. J. Bograd, E. L. Hazen & D. G. Foley 
University of California, Santa Cruz, Department of Ecology & Evolutionary Biology, Long Marine Laboratory, Santa Cruz, California 95060, USAG. A. Breed, A.-L. Harrison, M. J. Weise, R. W. Henry & D. P. Costa 
NOAA Southwest Fisheries Science Center, Fisheries Research Division, La Jolla, California 92037, USA
H. Dewar 
Oregon State University, Hatfield Marine Science Center, Newport, Oregon 97365, USA
B. R. Mate 
Inter-American Tropical Tuna Commission, La Jolla, California 92037, USA
K. M. Schaefer 
NOAA Southwest Fisheries Science Center, Protected Resources Division, La Jolla, California 92037, USA
S. R. Benson 

ABSTRACT

Pelagic marine predators face unprecedented challenges and uncertain futures. Overexploitation and climate variability impact the abundance and distribution of top predators in ocean ecosystems1, 2, 3, 4. Improved understanding of ecological patterns, evolutionary constraints and ecosystem function is critical for preventing extinctions, loss of biodiversity and disruption of ecosystem services. 

Recent advances in electronic tagging techniques have provided the capacity to observe the movements and long-distance migrations of animals in relation to ocean processes across a range of ecological scales5, 6. Tagging of Pacific Predators, a field programme of the Census of Marine Life, deployed 4,306 tags on 23 species in the North Pacific Ocean, resulting in a tracking data set of unprecedented scale and species diversity that covers 265,386 tracking days from 2000 to 2009. 

Here we report migration pathways, link ocean features to multispecies hotspots and illustrate niche partitioning within and among congener guilds. Our results indicate that the California Current large marine ecosystem and the North Pacific transition zone attract and retain a diverse assemblage of marine vertebrates. 

Within the California Current large marine ecosystem, several predator guilds seasonally undertake north-south migrations that may be driven by oceanic processes, species-specific thermal tolerances and shifts in prey distributions. We identify critical habitats across multinational boundaries and show that top predators exploit their environment in predictable ways, providing the foundation for spatial management of large marine ecosystems.

Figures at a glance
  1.. Figure 1: All TOPP species state space position estimates and distribution from electronic tagging.  
  a, Daily mean position estimates (circles) and annual median deployment locations (white squares) of all tagged species. b, Daily mean position estimates of the major TOPP guilds (from left): tunas (yellowfin, bluefin and albacore), pinnipeds (northern elephant seals, California sea lions and northern fur seals), sharks (salmon, white, blue, common thresher and mako), seabirds (Laysan and black-footed albatrosses and sooty shearwaters), sea turtles (leatherback and loggerhead) and cetaceans (blue, fin, sperm and humpback whales).

  2.. Figure 2: Fidelity and attraction to the CCLME.  
  a, Examples of pelagic predators released and electronically tracked in the CCLME that show fidelity to deployment locations and the CCLME. We show the release locations (square), pop-up satellite end point locations (triangle) and daily mean positions (circles) of the following species: yellowfin tuna (yellow), bluefin tuna (white), white shark (red), elephant seal (blue) and salmon shark (orange). b, Individual tracks of pelagic animals released >2,000?km away from the CCLME that are indicative of cross-basin or ecosystem attraction to, and temporary residency within, the eastern North Pacific. Symbols are as in a, for leatherback sea turtles (green), sooty shearwaters (pink), fur seals (pale yellow), black-footed albatrosses (black) and salmon sharks (orange).

  3.. Figure 3: Latitudinal migration cycles and seasonal climatologies within the CCLME.  
  a, Monthly mean latitudes of predators residing within or migrating to the CCLME. Black line segments denote gaps where no data were available. Sample sizes indicate the numbers of individual tracks contributing to the time series. b, Seasonal climatologies in the California Current for tunas (Pacific bluefin, blue; yellowfin, black), sharks (salmon shark, brown; shortfin mako, black; white shark, blue) and blue whales relative to median chlorophyll a densities and SST values between 2000 and 2009.

  4.. Figure 4: Predator density maps and residency patterns.  
  a, Density of large marine predators within the eastern North Pacific. Densities of the time-weighted and species-normalized position estimates of all tagged individuals were summed within 1°?×?1° grid cells. b, Density of large marine predators within the CCLME at a 0.25°?×?0.25° resolution. c, Patterns of resident (slow, area-restricted movements) versus transient (fast, directed movements) behaviours of predators that primarily occupied or migrated to the CCLME, estimated using a switching state-space model. The coloured points grading from blue to yellow display the posterior mean probability of the resident behaviour associated with each daily mean position estimate. Each panel displays residency patterns for ten individuals. Uncertainty in position estimates in a and b is included by calculating densities using all 2000 Markov chain Monte Carlo samples from the joint posterior distributions of the daily positions, rather than using only the posterior means. SST contours in a are denoted by solid white lines. Exclusive economic zones are delineated by solid black lines.

  5.. Figure 5: Niche separation within three predator guilds. 
------------ próxima parte ------------
Se ha borrado un adjunto en formato HTML...
URL: <http://lista.oannes.org.pe/pipermail/oannes-oannes.org.pe/attachments/20110706/18ca0a7f/attachment.htm>
------------ próxima parte ------------
A non-text attachment was scrubbed...
Name: no disponible
Type: image/jpeg
Size: 27246 bytes
Desc: no disponible
URL: <http://lista.oannes.org.pe/pipermail/oannes-oannes.org.pe/attachments/20110706/18ca0a7f/attachment.jpeg>
------------ próxima parte ------------
A non-text attachment was scrubbed...
Name: no disponible
Type: image/jpeg
Size: 36014 bytes
Desc: no disponible
URL: <http://lista.oannes.org.pe/pipermail/oannes-oannes.org.pe/attachments/20110706/18ca0a7f/attachment-0001.jpeg>
------------ próxima parte ------------
A non-text attachment was scrubbed...
Name: no disponible
Type: image/jpeg
Size: 24281 bytes
Desc: no disponible
URL: <http://lista.oannes.org.pe/pipermail/oannes-oannes.org.pe/attachments/20110706/18ca0a7f/attachment-0002.jpeg>
------------ próxima parte ------------
A non-text attachment was scrubbed...
Name: no disponible
Type: image/jpeg
Size: 24090 bytes
Desc: no disponible
URL: <http://lista.oannes.org.pe/pipermail/oannes-oannes.org.pe/attachments/20110706/18ca0a7f/attachment-0003.jpeg>
------------ próxima parte ------------
A non-text attachment was scrubbed...
Name: no disponible
Type: image/jpeg
Size: 45671 bytes
Desc: no disponible
URL: <http://lista.oannes.org.pe/pipermail/oannes-oannes.org.pe/attachments/20110706/18ca0a7f/attachment-0004.jpeg>