Acoustic scattering layers are ubiquitous, horizontally extensive aggregations of both vertebrate and invertebrate organisms that play key roles in oceanic ecosystems. However, currently there are no conventions or widely adaptable automatic methods for identifying these often dynamic, spatially complex features, so it is difficult to consistently and efficiently describe and...
To measure organismal coherence in a pelagic ecosystem, we used moored sensors to describe the vertical dynamics of each step in the food chain in shelf waters off the west shore of Oahu, Hawaii. Horizontally extensive, intense aggregations of phytoplankton, zooplankton, and micronekton exhibited strong diel patterns in abundance and...
Matlab code is included for detecting and tracking acoustic scattering layers from processed Echoview data. Acoustic scattering layers are ubiquitous, horizontally extensive aggregations of both vertebrate and invertebrate organisms that play key roles in oceanic ecosystems. However, currently there are no conventions or widely adaptable automatic methods for identifying these...
We hypothesized that changes in southeastern Bering Sea foraging conditions for black-legged kittiwakes (Rissa tridactyla)
have caused shifts in habitat use with direct implications for population trends. To test this, we compared at-sea
distribution, breeding performance, and nutritional stress of kittiwakes in three years (2008–2010) at two sites in the...
We use density and microstructure data to characterize the properties and physical setting of optical thin layers observed over the New Jersey shelf in the summer of 2006. Layers were differentiated into two types by their vertical position in the water column, fluorescence intensity, and possibly community composition or cell...
We examined the characteristics of biological patches at four different locations to assess the relationship of patch vertical scale, amplitude, and persistence. In contrast to patches of larger animals, we found that the majority of coherent aggregations of plankton at each site were vertically compressed, with most smaller than 5m...
We sought to characterize the distribution of juvenile walleye pollock Theragra chalcogramma in an area of intense predator-prey interactions and to describe habitat features that lead to their observed distributions. The distribution of juvenile walleye pollock around the Pribilof Islands in the southeastern Bering Sea in 2008 and 2009 was...
Marine prey often occur in hierarchical mosaics whereby small, high-density patches
are nested inside of larger, lower density aggregations. We tested the extent to which the foraging
behavior of a marine predator (northern fur seal Callorhinus ursinus) could be explained by the
hierarchical patch structure of a dominant prey species...
Spatial coherence between predators and prey has rarely been observed in pelagic marine ecosystems. We used measures of the environment, prey abundance, prey quality, and prey distribution to explain the observed distributions of three co-occurring predator species breeding on islands in the southeastern Bering Sea: black-legged kittiwakes (Rissa tridactyla), thick-billed...
The importance of spatial pattern in ecosystems has long been recognized. However, incorporating patchiness into our understanding of forces regulating ecosystems has proven challenging. We used a combination of continuously sampling moored sensors complemented by shipboard sampling to measure the temporal variation, abundance, and vertical distribution of four trophic levels...