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Graham, MH, Dayton PK, Erlandson JM.  2003.  Ice ages and ecological transitions on temperate coasts. Trends in Ecology & Evolution. 18:33-40.   10.1016/s0169-5347(02)00006-x   AbstractWebsite

Organisms face continual fluctuations in global climatic processes to which they must adapt or perish. Considering that many species are key habitat formers and energy producers, such responses to climate change can have significant population, community and even ecosystem consequences. Paleo-records of ecosystem responses to past environmental variability have proven invaluable for studying impacts of climate change on natural systems, yet such records are almost completely lacking for temperate benthic marine systems. Here, we bring together recent advances in palleoclimatology, coastal geomorphology, paleoceanography and archaeology for a well-studied region (the Southern California Bight, USA). We argue that there is now enough evidence to show that late-Quaternary sea-level rise over the past 18 500 years has caused a large-scale ecological shift in this region from highly productive rocky reefs to less productive sandy shores. Our integrated approach has implications for other temperate coastlines and helps provide insight into the interactions between human culture, biological communities and their environments.

Thrush, SF, Hewitt JE, Cummings VJ, Dayton PK.  1995.  The impact of habitat disturbance by scallop dredging on marine benthic communities: What can be predicted from the results of experiments? Marine Ecology-Progress Series. 129:141-150.   10.3354/meps129141   AbstractWebsite

Field experiments were conducted on 2 subtidal sandflats to identify the short-term impacts of commercial scallop dredging on macrobenthic communities. The 2 sites (1400 m(2)) were situated 14 km apart, both at about 24 m depth, with similar exposure aspects and were characterised by infaunal communities dominated by small and short-lived species. Prior to dredging, preliminary sampling failed to reveal significant differences in the density of common macrofauna within each site, although community composition was distinctly different between sites. The experiment was initiated by using a commercial scallop dredge to dredge half of each study site. Macrofauna samples were collected in both the dredged and adjacent reference plot at each site immediately after dredging and again 3 mo later. The density of common macrofaunal populations at each site decreased as a result of dredging, with some populations still significantly different from the adjacent reference plot after 3 mo. Significant compositional differences in the assemblage structure between dredged and reference plots were also recorded at each site over the course of the experiment. The findings of this experiment are considered a conservative assessment of bottom disturbance by fishing because of the area of seabed used, the types of community present and the intensity of disturbance used in the experiment. The findings of this and similar short-term experiments are discussed in light of the need to predict and assess possible large-scale changes to benthic communities as a result of habitat disturbance by fishing.

Kaufman, L, Dayton PK.  1997.  Impacts of marine resource extraction on ecosystem services and sustainability. Nature's services: societal dependence on natural ecosystems. ( Daily GC, Ed.).:275-293., Washington, DC: Island Press AbstractWebsite
Dayton, PK, Robilliard GA.  1971.  Implications of pollution to McMurdo Sound benthos. Antarctic Journal of the United States. 6:53-56. AbstractWebsite
Birkeland, C, Dayton PK.  2005.  The importance in fishery management of leaving the big ones. Trends in Ecology & Evolution. 20:356-358.   10.1016/j.tree.2005.03.015   AbstractWebsite

Research by Berkeley et al. and by Bobko and Berkeley has recently demonstrated that older individuals of some fish species produce larvae that have substantially better survival potential than do larvae from younger fishes. These new findings augment established knowledge that larger individuals usually have exponentially greater fecundity. This is important because commercial fisheries and especially recreational fishing often target the larger fish. The protection of larger or older individuals is necessary for the sustainability of species currently exploited by humans.

Dayton, PK, Tegner MJ.  1984.  The importance of scale in community ecology: a kelp forest example with terrestrial analogs. A New ecology: novel approaches to interactive systems. ( Price PW, Slobodchikoff CN, Gaud WS, Eds.).:457-481., New York: Wiley Abstract
Dayton, PK.  2003.  The importance of the natural sciences to conservation. American Naturalist. 162:1-13.   10.1086/376572   AbstractWebsite

The last century has seen enormous environmental degradation: many populations are in drastic decline, and their ecosystems have been vastly altered. There is an urgent need to understand the causes of the decline, how the species interact with other components of the environment, and how ecosystem integrity is determined. A brief review of marine systems emphasizes the importance of natural sciences to understanding the systems and finding solutions. These environmental crises coincide with the virtual banishment of natural sciences in academe, which eliminate the opportunity for both young scientists and the general public to learn the fundamentals that help us predict population levels and the responses by complex systems to environmental variation. Science and management demands that complex systems be simplified, but the art of appropriate simplification depends on a basic understanding of the important natural history. It seems unlikely that meaningful conservation and restoration can be accomplished unless we recover the tradition of supporting research in and the teaching of natural history. We must reinstate natural science courses in all our academic institutions to insure that students experience nature first-hand and are instructed in the fundamentals of the natural sciences.

Dayton, PK.  1989.  Interdecadal variation in an antarctic sponge and its predators from oceanographic climate shifts. Science. 245:1484-1486.   10.1126/science.245.4925.1484   AbstractWebsite

During the 1960s there was extensive formation of anchor ice to depths of 30 meters at McMurdo Station, Antarctica. During this period the sponge Homaxinella balfourensis was rare, as were its predators in that depth zone. Most of the existing sponges were killed by anchor ice. During the 1970s, anchor ice formation was reduced, and there was a massive recruitment of Homaxinella, which covered as much as 80 percent of the substrata in that zone. Many predators appeared but did not control the sponge population, and it continued to grow through that decade. The early 1980s were characterized by ice formation and almost all of the Homaxinella were eliminated, leaving an order of magnitude more predators in that zone. The interdecadal increases in anchor ice probably result from local upwelling of extremely cold deep water, possibly in response to shifts in the strengths of regional currents.

Tegner, MJ, Dayton PK, Edwards PB, Riser KL.  1996.  Is there evidence for long-term climatic change in southern California kelp forests? California Cooperative Oceanic Fisheries Investigations Reports. 37:111-126. AbstractWebsite

Evidence for long-term natural change in coastal ecosystems has to be separated from the effects of intense anthropogenic impacts, especially in heavily populated areas. The kelp forests of southern California, highly productive ecosystems organized around the giant kelp, Macrocystis pyrifera, support a variety of fisheries, and the kelp is harvested for extraction of alginates. Because of the importance of Macrocystis itself to the diverse assemblage within the kelp forest community, research in this ecosystem has focused on changes in giant kelp populations. Canopy maps of the Point Loma kelp forest near San Diego illustrate major changes over the last century; these changes have been ascribed to a variety of different causes, including temperature. To understand the role of physical forcing on interannual variability in the Macrocystis canopy at Point Loma, we compared two 31-year kelp data sets with available physical records. Annual average surface temperature was significantly correlated with kelp harvest, but explained only 24% of the variance. Because the canopy of giant kelp is susceptible to disturbances that may not affect plant survival, we evaluated two subsurface measures-stipe number as an index of individual plant growth, and stipe density as a measure of carrying capacity. Both stipe measures were sensitive to interannual variability in surface temperature for the period 1983-95 and were more sensitive than plant survival. Plant size and carrying capacity were very low following 1992-93 El Nino conditions and the anomalously warm 1994. Comparison with historical stipe data from 1957, 1973, and 1974 indicates up to two-thirds reductions in standing biomass since 1957. There is a strong inverse trend between median plant size and the sums of anomalies in Scripps Institution of Oceanography Pier surface temperature, calculated quarterly for three years. It appears, however, that these large, interdecadal changes in biomass can be explained by the location of the data sets within multiyear warm and cold periods. We conclude that stipe numbers and stipe density--measures of individual plant size and carrying capacity--are useful tools for evaluating long-term change in Macrocystis populations within specific locations. Although limited by the paucity of historical observations, the sensitivity of stipe counts to surface temperature argues strongly for their incorporation into ongoing and future kelp forest research.