TY - JOUR
T1 - Delayed recovery of giant kelp near its southern range limit in the North Pacific following El Niño
AU - Edwards, M. S.
AU - Hernández-Carmona, G.
N1 - Funding Information:
Acknowledgements We thank our many assistants without whose help the fieldwork would not have been possible. We are grateful to M. Kenner and J. Estes for their logistical support during the early stages of this project and to D. Canestro, P. Dal Ferro, and S. Cla-beusch for their assistance with diving activities. We thank M. Kailey for moral support in the field and Tony and Edith for their excellent fish tacos. We are also grateful to the fishing cooperatives at Punta San Roque, Punta Eugenia, and Punta San Hipólito for their generous assistance with logistical matters and E. Danner and M. Tinker for help with imagery. This work was supported in part by grants from UC Mexus and the PADI Foundation to M. Edwards and CONACYT (4113000-5-029PN-1297) to G. Hernández. G. Her-nández is Becario of the programs COFAA-IPN and EDI-IPN.
PY - 2005/5
Y1 - 2005/5
N2 - The northern distribution limit of giant kelp, Macrocystis pyrifera (Agardh), along the Pacific coast of North America is relatively stable near Point Año Nuevo, California, but its southern limit has varied over hundreds of kilometers along the Baja California peninsula during the past 20 years. The factors that drive this variability in the southern limit were examined by: (1) quantifying the abundances of M. pyrifera and the subsurface stipitate kelp, Eisenia arborea (Areschoug), near M. pyrifera's then southern limit at Punta San Roque (27°15′N; 114°42′W) on ten occasions between August 1997 and June 2002 (prior to and following the 1997/1998 El Niño Southern Oscillation); (2) initiating a field manipulation at Punta San Roque in June 2000 to examine competition between these two kelp species; and (3) surveying 20 additional sites near Punta San Hipólito (27°01′N; 114°00′W) in June 2002 to determine whether M. pyrifera populations had recovered to their pre-1982/1983 El Niño southern range limit after ∼20 years of absence. These observations and the experimental results suggest that M. pyrifera is removed from its southern limit by the high temperatures and large waves associated with El Niños, while E. arborea is able to survive and recruit in high densities and thereby delay or even prevent M. pyrifera's recovery. An inverse relationship was observed between these two species over the 5-year study. The field experiment showed that at both 4 months and 1 year after areas occupied by E. arborea were cleared, substantial recruitment of M. pyrifera occurred, while recruitment was negligible in uncleared areas. This study suggests that the southern range limit of M. pyrifera is determined by increased mortality and recruitment failure following the warm temperatures and low nutrient conditions associated with El Niños, limited substrate availability, and by competition with the more persistent populations of E. arborea.
AB - The northern distribution limit of giant kelp, Macrocystis pyrifera (Agardh), along the Pacific coast of North America is relatively stable near Point Año Nuevo, California, but its southern limit has varied over hundreds of kilometers along the Baja California peninsula during the past 20 years. The factors that drive this variability in the southern limit were examined by: (1) quantifying the abundances of M. pyrifera and the subsurface stipitate kelp, Eisenia arborea (Areschoug), near M. pyrifera's then southern limit at Punta San Roque (27°15′N; 114°42′W) on ten occasions between August 1997 and June 2002 (prior to and following the 1997/1998 El Niño Southern Oscillation); (2) initiating a field manipulation at Punta San Roque in June 2000 to examine competition between these two kelp species; and (3) surveying 20 additional sites near Punta San Hipólito (27°01′N; 114°00′W) in June 2002 to determine whether M. pyrifera populations had recovered to their pre-1982/1983 El Niño southern range limit after ∼20 years of absence. These observations and the experimental results suggest that M. pyrifera is removed from its southern limit by the high temperatures and large waves associated with El Niños, while E. arborea is able to survive and recruit in high densities and thereby delay or even prevent M. pyrifera's recovery. An inverse relationship was observed between these two species over the 5-year study. The field experiment showed that at both 4 months and 1 year after areas occupied by E. arborea were cleared, substantial recruitment of M. pyrifera occurred, while recruitment was negligible in uncleared areas. This study suggests that the southern range limit of M. pyrifera is determined by increased mortality and recruitment failure following the warm temperatures and low nutrient conditions associated with El Niños, limited substrate availability, and by competition with the more persistent populations of E. arborea.
UR - http://www.scopus.com/inward/record.url?scp=18844434340&partnerID=8YFLogxK
U2 - 10.1007/s00227-004-1548-7
DO - 10.1007/s00227-004-1548-7
M3 - Artículo
SN - 0025-3162
VL - 147
SP - 273
EP - 279
JO - Marine Biology
JF - Marine Biology
IS - 1
ER -