University of California

Human activities, climate changes affect marine populations


Louis W. Botsford

Author Affiliations

L.W. Botsford is Professor, Department of Wildlife, Fish, and Conservation Biology, UC Davis.

Publication Information

Hilgardia 51(4):36-44. DOI:10.3733/ca.v051n04p36. July 1997.

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Upwelling of nutrient-rich waters makes California's coastal ocean one of the most productive in the world. Better understanding of the year-to-year changes in populations due to El Niños, and recent awareness of decade-to-decade widespread changes in the ocean and atmosphere, have improved our ability to project the effects of fishing and climate change on marine populations. On smaller scales, we are also finding that weekly changes in upwelling winds cause coastal currents to deliver planktonic larvae to the coast in spatial patterns. Additional research is vitally needed to reduce the uncertainty in population prediction that allows political pressure to lead to overfishing and confounds recovery planning for endangered species such as salmon.


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Botsford L. 1997. Human activities, climate changes affect marine populations. Hilgardia 51(4):36-44. DOI:10.3733/ca.v051n04p36
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