Associations between seabirds and water-masses in the northern Pacific Ocean in summer

Wahl, Terence R.; Ainley, David G.; Benedict, Alia; DeGange, Anthony R.

doi:10.1007/bf00391059

Cited by 45 publications

(31 citation statements)

References 26 publications

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“…Elevated abundance of seabirds is found in areas characterized by high production or accumulation of biological matter, such as in frontal areas delineating different water masses (Abrams 1985, Wahl et al 1989, Pakhomov & McQuaid 1996, Hyrenbach et al 2007), along the continental edge (Hay 1992, Piatt et al 2006, or in inshore waters (Harrison et al 1994). On a smaller scale, local interactions between currents and the sea bottom may structure water masses into zones with different properties.…”

Section: Spatial Handicaps Of Preymentioning

confidence: 99%

“…One ecological interaction that can impose a spatial constraint is interspecific competition, which can reduce the realized niche of a predator and therefore potentially constrain its habitat use (Chase & Leibold 2003). Different seabird species have different adaptations and are consequently associated with different parts of the pelagic ecosystem (Abrams 1985, Wahl et al 1989, Ainley et al 1992, Harrison et al 1994, Ballance et al 1997, Vilchis et al 2006. For example, in the eastern tropical Pacific, Ballance et al (1997) identified 3 distinct seabird assemblages associated with areas of different productivity.…”

Section: Spatial Handicaps Of Predatorsmentioning

confidence: 99%

See 1 more Smart Citation

Spatial interaction between seabirds and prey: review and synthesis

Fauchald¹

2009

Mar. Ecol. Prog. Ser.

149

142

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The Ideal Free Distribution theory predicts a close spatial match between predators and prey. Studies have shown that seabird and prey distribution seldom conforms with this prediction. In this study, I review recent theoretical advances in spatial predator-prey interactions and relate these with studies of seabirds and pelagic schooling fish and crustaceans. Studies on seabirds and prey have generally assumed that prey are nonresponsive. Predator-prey interactions should, however, be viewed as a 2-way spatial game where seabirds track concentrations of prey while prey move away from areas with high risk of predation. The outcome of the game depends on how seabirds and prey are spatially constrained. Constraints include the spatial distribution of resources, interspecific competition, the location of spawning and breeding areas, and limitations on diving depth. Although game theoretic models can explain some general aspects of the spatial interaction, the spatial distribution of seabirds and prey is generally much more aggregated and elusive than can be expected from the game theoretic equilibrium. This is because spatial pattern is formed through selforganizing behavior that includes schooling, local enhancement and area-restricted search (ARS). Schooling and local enhancement are processes with strong positive density dependence that destabilize the predator-prey interaction locally. However, the unstable local dynamics might be stabilized by spatial constraints and the effects of ARS processes at large scales.

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Section: Spatial Handicaps Of Preymentioning

confidence: 99%

Section: Spatial Handicaps Of Predatorsmentioning

confidence: 99%

Spatial interaction between seabirds and prey: review and synthesis

Fauchald¹

2009

Mar. Ecol. Prog. Ser.

149

142

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“…For example, studies have quantified seabird habitat using physical parameters describing water masses, e.g. temperature and salinity (King 1974, Pocklington 1979, Ainley & Boekelheide 1983, Wahl et al 1989. Physical proxies for seabird distribution and abundance should include more than just temperature and salinity, since seabird habitat selection is most likely a function of prey abundance and/or availability and comprised of a mosaic of environmental variables.…”

Section: Introductionmentioning

confidence: 99%

Pelagic habitat of seabirds in the eastern tropical Pacific: effects of foraging ecology on habitat selection

Vilchis¹,

Ballance²,

Fiedler³

2006

Mar. Ecol. Prog. Ser.

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A central tenet of ecology is the quantification of species-habitat relationships in order to explain spatial variability in the distribution and abundance patterns of animals. We quantified habitat preferences for 6 tropical seabird species representing a phylogenetically and ecologically diverse group within the eastern tropical Pacific (ETP). Seabird censuses were conducted aboard NOAA research vessels from August to November of 1989 and 1990 using 300 m strip transect methods. Simultaneously with the seabird censuses and from the same ships, oceanic habitat was quantified by measuring sea surface temperature, salinity, and chlorophyll, as well as thermocline depth and strength. We quantified seabird habitat using generalized additive models fitted with forward and backward selection algorithms based on minimizing the Akaike information criterion (AIC). In general, seabird habitat models performed well in explaining spatial variability in abundance, reducing the null deviance to ranges between 42.8 and 73.5%, and predicting seabird density patterns with an accuracy ranging from 56.6 to 80.5%. Relative abundance of the species modeled affected the outcome: the higher the abundance, the more robust the fit. Seabirds feeding on fishes and squids associated with habitats characterized by deep (>100 m) and strong (> 2°C 10 m -1 ) thermoclines, while planktivorous species preferred habitat characterized by shallower thermoclines with cooler surface temperatures (< 25°C) and a less stratified water column. Thus, seabirds in different feeding guilds have clear and distinct habitat preferences within the ETP. We propose thermocline topography as a key variable in predicting distribution and abundance of seabirds in this area, probably due to its influence on the availability of seabird prey.

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“…The 'classical' age of at-sea investigation of seabirds occurred during the 1970-90s, when extensive data from shipping and other vessels were collected. During this period, there were major discoveries of the association of seabirds and seabird communities with specific oceanographic features (Brown et al 1975, Pocklington 1979, Briggs et al 1987, Wahl et al 1989, and frontal zones at large spatial scales (Schneider et al 1987), as well as more fine-scale features (e.g. Hunt & Schneider 1987, Louzao et al 2006) at smaller scales (Hunt & Harrison1990, Hunt 1991.…”

Section: At-sea Spatial Ecologymentioning

confidence: 99%