Assimilation efficiency and growth of Rhinoceros Auklet chicks fed with Japanese Sand Lance and krill

We studied (1984–86) the diet of rhinoceros auklet (Cerorhinca monocerata) nestlings at three colonies on the British Columbia coast (Lucy islands, Pine Island, and Triangle Island). On the Lucy Islands, Pacific sand lance (Ammodytes hexapterus) dominated nestling food loads in all years. In 1985, 0+ sand lance dominated the nestling diet on all colonies. Concurrent measures of nestling growth rate, independent indexes of ocean production, and the proportion of sand lance in groundfish stomach samples were also highest in 1985. This suggests a linkage between ocean production, 0+ sand lance abundance, and events on seabird colonies over a broad geographic range. We emphasize the importance of sand lance to temperate seabirds and contrast British Columbia with areas where sand lance are commercially exploited. Rhinoceros auklet nestling diet, growth, and other data collected on colonies suggest that long-term monitoring on seabird colonies can contribute timely and inexpensive information on the recruitment of sand lance stocks in Canadian waters.

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Intra-seasonal and inter-annual patterns in the demographics of sand lance and response to environmental drivers in the North Pacific

Marine Ecology Progress Series ◽

10.3354/meps12897 ◽

2019 ◽

Vol 617-618 ◽

pp. 221-244 ◽

Cited By ~ 5

Author(s):

MR Baker ◽

ME Matta ◽

M Beaulieu ◽

N Paris ◽

S Huber ◽

...

Keyword(s):

North Pacific ◽

Environmental Drivers ◽

Sand Lance ◽

The North ◽

The North Pacific ◽

Annual Patterns

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Cysts of unknown etiology in marine fishes of the Northwest Atlantic and Gulf of Mexico

Canadian Journal of Zoology ◽

10.1139/z87-046 ◽

1987 ◽

Vol 65 (2) ◽

pp. 296-303 ◽

Cited By ~ 12

Author(s):

Sharon A. MacLean ◽

Carol M. Morrison ◽

Robert A. Murchelano ◽

Sherie Everline ◽

Joyce J. Evans

Keyword(s):

Unknown Etiology ◽

Ground Substance ◽

Structural Components ◽

Electron Microscopic ◽

Sand Lance ◽

Atlantic Mackerel ◽

The Core ◽

Sudan Black B ◽

Silver Hake ◽

Feulgen Technique

Results of light and electron microscopic examinations of cysts of unknown etiology (CUEs) occurring in the gills of Atlantic mackerel, red hake, white hake, cod, haddock, and silver hake are presented. CUEs were found also in gills and viscera of winter flounder, Atlantic croaker, spot, windowpane flounder, and sand lance. CUEs measured 150–400 μm in diameter and consisted of an external fibrous cuticle, usually a thick median band, and a central core that frequently contained eosinophilic vesicles. Structures resembling mitochondria were found in the band and in vesicles of the core, but no other organelles were apparent. Cytochemical staining and ultramicroscopy revealed aggregates of glycogen in the core ground substance; no structural components were stained with Sudan black B or by the Feulgen technique. Extensive encapsulation of CUEs by fibroblasts was typical. Of 717 mackerel examined, 76.8% had CUEs in the gills; numbers ranged from 1 to 353 per fish. The prevalence and intensity of occurrence of CUEs increased with the age of the mackerel.

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Significance of Organic Detritus in the Diet of Larval Lampreys in the Great Lakes Basin

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f94-239 ◽

1994 ◽

Vol 51 (11) ◽

pp. 2380-2387 ◽

Cited By ~ 72

Author(s):

Trent M. Sutton ◽

Stephen H. Bowen

Keyword(s):

Great Lakes ◽

Feeding Rate ◽

Assimilation Efficiency ◽

Dry Mass ◽

Great Lakes Basin ◽

Organic Detritus ◽

Upper Peninsula ◽

Sea Lampreys ◽

Gut Fullness ◽

Upper Peninsula Of Michigan

Larval sea lamprey (Petromyzon marinus) and northern brook lamprey (Ichthyomyzon fossor) were collected monthly from three streams in the Upper Peninsula of Michigan from May 1992 through May 1993 and larval sea lampreys were collected during summer months from sites throughout the Great Lakes basin. Organic detritus made up most of the diet ash-free-dry-mass (AFDM) throughout the year, averaging 97.79%, with algae (2.12%) and bacteria (0.09%) making up the remainder of the diet AFDM. Assimilation efficiency for AFDM averaged 72% during warmer months and 53% during cooler months (annual mean = 61%). Gut fullness (amount of AFDM in the anterior one-tenth of the intestine) was low (mean = 0.10 mg diet AFDM∙g−1 ammocoete). There were no significant differences in these measures between ammocoetes collected from the Upper Peninsula and those collected throughout the Great Lakes basin. From a laboratory-determined relationship between gut fullness and feeding rate, feeding rate in the field was estimated to be extremely slow, ranging from 4.2 to 5.5 mg diet AFDM∙g−1 ammocoete∙d−1. These observations indicate that larval lampreys efficiently utilize a diet of organic detritus during warmer months when stream temperatures and food quality are more favorable for feeding, digestion, and growth.

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A hierarchical modelling approach to estimating humpback whale abundance from sand lance abundance

Ecological Modelling ◽

10.1016/j.ecolmodel.2021.109662 ◽

2021 ◽

Vol 456 ◽

pp. 109662

Author(s):

Tammy L. Silva ◽

David N. Wiley ◽

Gavin Fay

Keyword(s):

Humpback Whale ◽

Sand Lance ◽

Hierarchical Modelling ◽

Modelling Approach

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Assimilation Efficiency

Encyclopedia of Entomology ◽

10.1007/0-306-48380-7_332 ◽

2006 ◽

pp. 207-207

Keyword(s):

Assimilation Efficiency

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Larval sand lance (Ammodytes sp.) in the diet of small juvenile wolffish (Anarhichas spp.): predatory interactions in frontal water masses off western Greenland

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f02-147 ◽

2002 ◽

Vol 59 (11) ◽

pp. 1759-1767 ◽

Cited By ~ 10

Author(s):

Peter Munk

Keyword(s):

Fish Larvae ◽

Stomach Contents ◽

Prey Type ◽

Ontogenetic Changes ◽

Sand Lance ◽

Larval Size ◽

Predatory Behaviour ◽

Dietary Shift ◽

Abundance Estimates ◽

Anarhichas Lupus

The predatory behaviour of two species of juvenile wolffish (Anarhichas lupus and Anarhichas minor) was studied during a field campaign across a frontal area off western Greenland. The study focused on ontogenetic changes in prey-type and -size preference of the wolffish and their predatory impact on a cohabiting population of larval sand lance (Ammodytes sp.). Sampling took place along a cross-shelf transect at latitude 66°20' N, and the analysis is based on stomach contents of assembled wolffish (25 cm in length) and abundance estimates of plankton and fish. An ontogenetic change in wolffish prey preference was evident as a dietary shift from copepods and smaller amphipods to larger amphipods and fish larvae. The inclusion of fish larvae in the wolffish diet led to a marked increase in prey biomass, and fish larvae constituted up to 77% of diet biomass in the largest juveniles caught. Wolffish selectively targeted the smaller-sized part of the larval sand lance population; hence, larval vulnerability increased with decreasing size. Comparison between estimated predation rates and abundances of predator and prey indicated larval predation mortalities of up to 5% per day, with mortality peaking in the vicinity of a hydrographic front. Hence, findings suggest substantial predation pressure on larvae, primarily related to larval size and distribution.

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