Effects of oiling on exercise physiology and diving behavior of river otters: a captive study

Following the Exxon Valdez oil spill (EVOS), river otters (Lontra canadensis) on oiled shores had lower body mass, selected different habitat characters, and had larger home ranges and less diverse diets than did otters living in non-oiled areas. We explored the possibility that these changes were due to the effect of crude oil contamination on physiological and behavioral processes in otters. Fifteen otters were exposed to two levels of oil contamination under captive controlled conditions at the Alaska Sealife Center in Seward, Alaska, U.S.A. We collected blood samples for hematological examinations and measured oxygen consumption in otters exercising on a motorized treadmill. We also observed diving and foraging behavior of otters offered live fish. Otters exposed to oil became anemic relative to controls. While oxygen consumption of resting river otters was not related to changes in hemoglobin concentration, exercising river otters with decreased hemoglobin levels displayed significantly increased oxygen consumption (P = 0.042). Oiled otters also performed fewer dives when chasing fish (P = 0.04), representing a potential decrease of 64% in the capture rate of prey. Our data strongly support the hypothesis that changes in prey types and home-range utilization by oiled river otters following EVOS were influenced by hematological changes, associated increases in energetic costs, and reduced diving ability.

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Spacing, movements, and habitat selection of the river otter in boreal Alberta

Canadian Journal of Zoology ◽

10.1139/z94-175 ◽

1994 ◽

Vol 72 (7) ◽

pp. 1314-1324 ◽

Cited By ~ 43

Author(s):

D. G. Reid ◽

T. E. Code ◽

A. C. H. Reid ◽

S. M. Herrero

Keyword(s):

Lontra Canadensis ◽

Home Ranges ◽

Adult Males ◽

Movement Rates ◽

River Otters ◽

Aquatic Mammal ◽

Adult Females ◽

Two Factors ◽

Bog Lakes ◽

Selection Of

Seasonal spacing patterns, home ranges, and movements of river otters (Lontra canadensis) were studied in boreal Alberta by means of radiotelemetry. Adult males occupied significantly larger annual home ranges than adult females. Males' ranges overlapped those of females and also each other's. In winter, home ranges of males shrank and showed less overlap. Otters often associated in groups, the core members typically being adult females with young, or adult males. Otters tended to be more solitary in winter. In winter, movement rates of all sex and age classes were similar, and much reduced for males compared with those in other seasons. These data indicated a strong limiting effect of winter ice on behaviour and dispersion. We tested the hypothesis that otters select water bodies in winter on the basis of the suitability of shoreline substrate and morphology for dens with access both to air and to water under ice. Intensity of selection was greatest in winter, with avoidance of gradually sloping shorelines of sand or gravel. Adults selected bog lakes with banked shores containing semi-aquatic mammal burrows, and lakes with beaver lodges. Subadults selected beaver-impounded streams. Apart from human harvest, winter habitats and food availability in such habitats are likely the two factors most strongly limiting otter density in boreal Alberta.

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Hematological Changes and Reference Intervals in Hanwoo Calves during the First 28 Weeks of Life

Animals ◽

10.3390/ani11061806 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1806

Author(s):

Ui-Hyung Kim ◽

Seung-Hwan Lee ◽

Sang-Rae Cho ◽

Sung-Sik Kang ◽

Shil Jin ◽

...

Keyword(s):

Hemoglobin Concentration ◽

Reference Intervals ◽

Mean Corpuscular Hemoglobin ◽

Blood Cell Count ◽

Platelet Volume ◽

Adult Cattle ◽

Male And Female ◽

Analytic Process ◽

Process Work ◽

Hematological Changes

Hematological reference intervals must consider several parameters, including genotype, age, sex, management, and analytic process. Work is needed to evaluate hematological changes specifically in Hanwoo calves and according to calf sex. Therefore, in this study, we sought to confirm the complete blood cell count (CBC) reference intervals in Hanwoo calves, to monitor changes in hematologic values in Hanwoo calves from birth until 28 weeks of life, and to compare the hematologic values of male and female calves. A total of 35 male calves and 35 female calves was studied. Calf blood was sampled at multiple intervals from the time of birth until 28 weeks of age (including within 6 h of birth and at 2 days, 7 days, and 4 weeks and then at 4-week intervals through 28 weeks). In addition, blood samples were collected from 210 clinically healthy pregnant Hanwoo cows to establish CBC reference intervals for adult cattle. There were significant differences in the results of the cows and calves in all 14 parameters considered. The CBC reference intervals of the calves were wider than those of the cows in all parameters except mean corpuscular volume, mean corpuscular hemoglobin concentration, and mean platelet volume. We also identified differences from birth through 28 weeks between male and female calves at only some ages and some parameters. These results suggest that CBC reference intervals specific to Hanwoo calves are necessary for accurate diagnosis of calf diseases.

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Effect of exposure to low temperature on normal and iron-deficient subjects

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1984.246.3.r380 ◽

1984 ◽

Vol 246 (3) ◽

pp. R380-R383 ◽

Cited By ~ 2

Author(s):

C. Martinez-Torres ◽

L. Cubeddu ◽

E. Dillmann ◽

G. L. Brengelmann ◽

I. Leets ◽

...

Keyword(s):

Oxygen Consumption ◽

Cold Exposure ◽

Initial Temperature ◽

Iron Status ◽

Hemoglobin Concentration ◽

Normal Subjects ◽

Plasma Norepinephrine ◽

Oral Temperature ◽

The Third ◽

Iron Deficient

Twenty-one Venezuelan peasants were segregated into three groups on the basis of measurements of iron status: seven normal subjects, six iron-deficient subjects with normal hemoglobin and eight iron-deficient subjects with a hemoglobin concentration of less than 9 g/dl. All subjects were placed in a water bath at an initial temperature of 36 degrees C. The water temperature was then rapidly lowered to 28 degrees C, and observations were made over the period of 1 h. Mean oral temperature of the first group fell 0.2, the second group 0.5, and the third group 0.9 degrees C. Mean plasma norepinephrine levels in both groups of iron-deficient subjects were significantly higher at 36 degrees C and during cold exposure compared with control subjects. Oxygen consumption was also significantly increased in both groups of iron-deficient subjects after cold exposure.

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Development of polymorphic microsatellite loci for North American river otters (Lontra canadensis) and amplification in related Mustelids

Molecular Ecology Notes ◽

10.1046/j.1471-8286.2003.00564.x ◽

2003 ◽

Vol 4 (1) ◽

pp. 56-58 ◽

Cited By ~ 31

Author(s):

Amanda S. Beheler ◽

Jennifer A. Fike ◽

Lisa M. Murfitt ◽

Olin E. Rhodes ◽

Thomas S. Serfass

Keyword(s):

North American ◽

Microsatellite Loci ◽

Lontra Canadensis ◽

River Otters ◽

American River ◽

Polymorphic Microsatellite

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A River Otter's, Lontra canadensis, Capture of a Double-crested Cormorant, Phalacrocorax auritus, in British Columbia's Gulf Island Waters

The Canadian Field-Naturalist ◽

10.22621/cfn.v121i3.483 ◽

2007 ◽

Vol 121 (3) ◽

pp. 325

Author(s):

Michael H. H. Price ◽

Clare E. Aries

Keyword(s):

Lontra Canadensis ◽

Phalacrocorax Auritus ◽

River Otter ◽

Freshwater Lakes ◽

Marine Bird ◽

River Otters

Direct and apparent predation events by River Otters (Lontra canadensis) on birds have been recorded on marine islands and freshwater lakes. We add to this the first known observation of a River Otter capturing a marine bird on the ocean.

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Fatty acid analysis as a tool to infer the diet in Illinois river otters (Lontra canadensis)

Journal of Animal Science and Technology ◽

10.1186/2055-0391-56-16 ◽

2014 ◽

Vol 56 (1) ◽

pp. 16 ◽

Cited By ~ 3

Author(s):

Damian Satterthwaite-Phillips ◽

Jan Novakofski ◽

Nohra Mateus-Pinilla

Keyword(s):

Fatty Acid ◽

Fatty Acid Analysis ◽

Lontra Canadensis ◽

Illinois River ◽

River Otters

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River Otter, Lontra canadensis, Food Habits in the Missouri Ozarks

The Canadian Field-Naturalist ◽

10.22621/cfn.v122i4.636 ◽

2008 ◽

Vol 122 (4) ◽

pp. 303 ◽

Cited By ~ 11

Author(s):

Nathan M. Roberts ◽

Charles F. Rabeni ◽

John S. Stanovick ◽

David A. Hamilton

Keyword(s):

Smallmouth Bass ◽

Lontra Canadensis ◽

Micropterus Dolomieu ◽

Widespread Occurrence ◽

River Otters ◽

Lepomis Megalotis ◽

Rock Bass ◽

Longear Sunfish ◽

The Mean ◽

Ambloplites Rupestris

The reintroduction of River Otters (Lontra canadensis) between 1982 and 1992 resulted in widespread occurrence of the species throughout the Missouri Ozarks. This study examined otter diets from the vicinity of two Ozark streams in relation to seasonal and spatial trends. Otter scats (N = 4750) were collected and analyzed from the Osage Fork River and Big Piney River during the summer and winter seasons of 2001 and 2002. During the winter (January-March), fish occurred in 86% of the samples. During the summer (June–August), occurrence of fish dropped to approximately 15% for both rivers. Seven families of fish were identified in the diets, with Centrarchidae being most common regardless of river or season. Within the Centrarchidae, the genus Lepomis (mostly Longear Sunfish, Lepomis megalotis) was most common, with Micropterus (mostly Smallmouth Bass, Micropterus dolomieu) and Rock Bass (Ambloplites rupestris) also well represented. The mean age of Ambloplites consumed (mean = 3.3 years) was consistently older than that of either Micropterus (mean = 2.54 years) or Lepomis (mean = 2.78 years). Crayfish were recovered from a mean of 85.2% of scats in the winter and 99% in the summer. Smaller fish and crayfish were more common from the upper reaches of the streams while larger fish were prevalent in the lower reaches.

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River Otter Distribution and Food Habits in Grand Teton National Park as Part of an Ongoing Project in the GYE

The UW National Parks Service Research Station Annual Reports ◽

10.13001/uwnpsrc.2015.4099 ◽

2015 ◽

Vol 38 ◽

pp. 75-78

Author(s):

Kelly Pearce ◽

Tom Serfass

Keyword(s):

National Park ◽

Activity Patterns ◽

Public Support ◽

Primary Objective ◽

Camera Traps ◽

Lontra Canadensis ◽

Flagship Species ◽

River Otter ◽

Grand Teton National Park ◽

River Otters

Grand Teton National Park is part of the known range of the North American river otter, however not much is known about this semi-aquatic mammal within the park. The results presented here are part of a larger project to investigate the potential of the river otter (Lontra canadensis) to serve as an aquatic flagship (species that engender public support and action) for the Greater Yellowstone Ecosystem. River otters, known for their charismatic behavior have the potential to serve as an aquatic flagship species to promote conservation of aquatic ecosystems. The primary objective of this portion of the study was to identify river otter latrines on portions of the Snake River, between Flagg Ranch and Jackson Lake, and between Jackson Lake Dam and Pacific Creek, collect river otter scats to determine diet of the river otter, and employ remote cameras to determine activity patterns of the river otters. Between 20 June and 1 July 2015, 26 river otter latrines were identified during shoreline surveys, 186 river otter scats were collected, and cameras were deployed at 6 latrines between 7 July and 24 August 2015. River otter scats have been cleaned and prepared for analysis, but have not all been processed to date. Camera traps recorded 222 images, of which 7% (n = 14) were of carnivores, 70% (n = 155) were of non-carnivore mammals, and 9% (n = 22) were of birds. River otters were detected at 1 of the 6 latrines, a total of 5 independent times during the study.

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