In-air and underwater vocalizations of eastern Canadian harbour seals, Phoca vitulina

2002 ◽  
Vol 80 (7) ◽  
pp. 1173-1179 ◽  
Author(s):  
Sofie M Van Parijs ◽  
Kit M Kovacs
Keyword(s):  
Phoca Vitulina ◽  
Nearest Neighbour ◽  
Adult Males ◽  
Mating Season ◽  
Agonistic Interactions ◽  
Age Classes ◽  
Harbour Seals ◽  
The World ◽  
Pinniped Species ◽  
Vocalization Type

Harbour seals, Phoca vitulina, have long been thought to be one of the least vocal pinniped species both in air and under water. However, recent studies have shown that males use underwater vocalizations intensively during the mating season. In air, harbour seals are still thought to be relatively silent. In this study we describe the vocal repertoire of Eastern Canadian harbour seals during the breeding season. Harbour seals from this area produced seven vocalization types in air and one vocalization type under water. In-air vocalizations are predominantly used by adult males during agonistic interactions. Other sex and age classes also vocalize, but less frequently. Nearest neighbour responses to in-air vocalizations were primarily agonistic when any age or sex class vocalized. In this study, seals produced an underwater roar vocalization closely resembling that produced by adult males during the mating season at other sites. Eastern Canadian harbour seals appear to be considerably more vocal when hauled out than is the norm for this species at other sites around the world.

scholarly journals Status of the harbour seal (Phoca vitulina) along the Murman coast of Russia

2010 ◽  
Vol 8 ◽  
pp. 37 ◽  
Author(s):  
Sergey V Zyryanov ◽  
Sergey A Egorov
Keyword(s):  
Activity Pattern ◽  
Daily Activity ◽  
Breeding Site ◽  
Phoca Vitulina ◽  
Adult Males ◽  
Breeding Colony ◽  
Harbour Seals ◽  
By Catch ◽  
Two Peaks ◽  
Gender Specific

Harbour seals are observed along the Murmansk coast of Russia, but they are not very abundant there. The estimated abundance for this area was about 500 individuals in 1998. The number of seals observed during winter months is less than during summer. During summer, the main habitats are the Pechenga inlet, the Motovsky and Kola Bays of the Western Murman coast and the Ivanovskaya Bay in the Eastern Murman coast. The Ivanovskaya Bay was thought to be the easternmost breeding colony of the subspecies Phoca vitulina vitulina. However, recent sightings may indicate the establishment of a breeding site further to the east, which then becomes the easternmost known habitat for this subspecies. A substantial, recent decrease in abundance has been observed in the Ivanovskaya Bay. The population numbered about 120 seals in the early 1990s, but only about 20 seals were seen in 2007 and 2008. It is presumed that the reasons for this reduction include hunting, fishery by-catch, disturbance and depletion of the food supply in this semi-enclosed inlet. A gender-specific daily activity pattern was observed in the IvanovskayaBay. The highest number of single animals (primarily adult males) hauled out during mid day, while hauled out females with pups showed two peaks per day associated with low tides.

Energy requirements for maintenance and growth of captive harbour seals, Phoca vitulina

1990 ◽  
Vol 68 (3) ◽  
pp. 423-426 ◽  
Author(s):  
Nina Hedlund Markussen ◽  
Morten Ryg ◽  
Nils Are Øritsland
Keyword(s):  
Body Weight ◽  
Energy Requirement ◽  
Phoca Vitulina ◽  
Metabolizable Energy ◽  
Age Classes ◽  
Maintenance Requirement ◽  
Harbour Seals ◽  
Significant Difference ◽  
Gross Energy ◽  
Ad Libitum

Four captive harbour seals were fed with herring both at restricted and at ad libitum levels during 1985 to 1988. The maintenance requirement, calculated from the x-intercept of the regression, was 194 ± 71 kcal∙kg body weight−0.75∙day−1. Assuming that metabolizable energy is 82.8% of gross energy, the maintenance requirement is 161 kcal∙kg body weight−0.75∙day−1. There was no significant difference in maintenance requirement between individuals or between age classes, and neither was there any significant difference between seasons. The gross energy requirement of growth was 909 kcal/100 g.

Dive shapes reveal temporal changes in the foraging behaviour of different age and sex classes of harbour seals (Phoca vitulina)

2002 ◽  
Vol 80 (9) ◽  
pp. 1569-1577 ◽  
Author(s):  
J Baechler ◽  
C A Beck ◽  
W D Bowen
Keyword(s):  
Foraging Behaviour ◽  
Direct Evidence ◽  
Function Analysis ◽  
Water Flux ◽  
Phoca Vitulina ◽  
Adult Males ◽  
Additional Information ◽  
Harbour Seals ◽  
And Function ◽  
The Relationship

Classifying dives into two-dimensional shapes based on time and depth is an attempt to extract additional information about the behaviour of aquatic air-breathing predators. In some species, there is considerable circumstantial evidence that different dive shapes represent different behaviours. However, few studies have provided direct evidence of the relationship between dive shape and function. We classified over 283 000 dives of adults (31 males and 45 females) and suckling (13) and recently weaned (15) harbour seal (Phoca vitulina) pups into seven shapes using supervised discriminant function analysis. Changes in the percentage of U-shaped dives over time within adults and weaned pups were associated with changes in food intake derived from water-flux studies on subsets of the same individuals. The changes in the percentage of U-shaped dives were accompanied by roughly reciprocal changes in V-shaped dives, whereas there was little change in other dive shapes, indicating that V-shaped dives are not generally exhibited during foraging. Video of adult males (from an animal-borne video system) also showed that there was a strong but not exclusive association between foraging and U-shaped dives. Our results indicate that changes in the percentage of U-shaped dives may serve as a reasonable index of changes in foraging behaviour. However, behaviours of suckling pups and adult males during the breeding season cannot be easily inferred from dive shape alone.

Display-area size, tenure length, and site fidelity in the aquatically mating male harbour seal, Phoca vitulina

2000 ◽  
Vol 78 (12) ◽  
pp. 2209-2217 ◽  
Author(s):  
Sofie M Van Parijs ◽  
Vincent M Janik ◽  
Paul M Thompson
Keyword(s):  
Comparative Analysis ◽  
Site Fidelity ◽  
Phoca Vitulina ◽  
Harbour Seal ◽  
Small Scale ◽  
Mating Season ◽  
Display Area ◽  
Harbour Seals ◽  
Acoustic Array ◽  
Number Of Males

Previous studies of the distribution and activity of male harbour seals, Phoca vitulina, based on telemetric techniques have shown that males restrict their range at the onset of the mating season and perform vocal and dive displays. While these data illustrated broad changes in male behaviour and distribution, they were not precise enough to reveal the extent to which individual males repeatedly return to the same locations to display. In this study we used an acoustic array to localise male vocalisations. This technique provided small-scale information on male behaviour over 3 consecutive years. This study provides the first details concerning display-area size in an aquatically mating phocid. Male vocalisations were located in two discrete areas each covering between 40 and 135 m2. Vocalisations were repeatedly located in these two areas over the 3-year period. Comparisons of four vocal parameters suggested that only one individual occupied each area throughout a mating season. Furthermore, comparative analysis suggested that males might return to the same two display areas in successive years. Although the number of males using the site was small, this study showed that acoustic localisation can be a valuable tool for detailed study of the underwater behaviour of aquatically mating pinnipeds.

Long-distance movements of harbour seals (Phoca vitulina) from a seasonally ice-covered area, the St. Lawrence River estuary, Canada

2004 ◽  
Vol 82 (7) ◽  
pp. 1070-1081 ◽  
Author(s):  
Véronique Lesage ◽  
Mike O Hammill ◽  
Kit M Kovacs
Keyword(s):  
River Estuary ◽  
Distribution Patterns ◽  
Phoca Vitulina ◽  
Harbour Seal ◽  
Adult Males ◽  
Long Distance ◽  
Adequate Food ◽  
Harbour Seals ◽  
Ice Conditions ◽  
St Lawrence River

Previous studies of harbour seal (Phoca vitulina L., 1758) movements indicate that this species is relatively sedentary throughout the year. However, few investigations have examined their movements and seasonal distribution patterns in ice-covered areas. This study used spatial analysis of ice data and movement data from harbour seals collected via satellite (n = 7) and VHF radiotelemetry (n = 15) to explore this species' spatial use patterns in a seasonally ice-covered region, the St. Lawrence River estuary, Canada. When solid ice formed within the bays of the estuary, four of the seven satellite-tagged animals (all adult males) left their summer haul-out areas, migrating 266 ± 202 km (range 65–520 km) to over-wintering sites. The seals exhibited preference for areas of light to intermediate ice conditions during the winter months; at least six of the seven seals occupied areas with lighter ice conditions than those that prevailed generally in the study area. Evidence of high abundance of potential prey for harbour seals in the estuary during winter suggests that reduced availability of adequate food resources is not the primary factor which influences the movement and distribution patterns of harbour seals. Movement patterns observed during the ice-free period concur with previously reported harbour seal behaviour; the seals remained near the coast (<6.1–11.0 km from shore) in shallow water areas (<50 m deep in 100% VHF and 90% SLTDRs (satellite-linked time-depth recorders)) and travelled only short distances (15–45 km) from capture sites. None of the VHF- or satellite-tagged seals crossed the 350 m deep Laurentian channel, which suggests that this deep body of water might represent a physical barrier to this coastal population.

Beneficiary and Adverse Effects of Phytoestrogens: A Potential Constituent of Plant Based Diet

2020 ◽  
Vol 26 ◽  
Author(s):  
Sridevi Vaadala ◽  
Naveen Ponneri ◽  
Venkat Shashank Karnam ◽  
Ramachandra Reddy Pamuru ◽  
Mohammed Arifullah
Keyword(s):  
Dairy Products ◽  
Metabolic Disorders ◽  
Hormone Replacement ◽  
Pharmaceutical Drugs ◽  
Adult Males ◽  
Flax Seed ◽  
Green Beans ◽  
The World ◽  
Pros And Cons ◽  
Derivatives Of

Background: Phytoestrogens are non-endocrine, non-steroidal secondary derivatives of plants and consumed through plant-based diet also named as “dietary estrogens”. The major sources of phytoestrogens are soy and soy-based foods, flax seed, chickpeas, green beans, dairy products, etc. The dietary inclusion of phytoestrogen based foods play a crucial role in the maintenance of metabolic syndrome cluster including obesity, diabetes, blood pressure, cancer, inflammation, cardiovascular diseases, postmenopausal ailments and their complications. In recent days, phytoestrogens are the preferred molecules for hormone replacement therapy. On the other hand, they act as endocrine disruptors via estrogen receptor mediated pathways. These effects are not restricted to adult males or females and identified even in development. Objective: Since phytoestrogenic occurrence is high at daily meal for most people from all over the world, they focused to study for its beneficiary effects towards developing pharmaceutical drugs for treating various metabolic disorders by keeping an eye on endocrine disruption. Conclusion: The present review emphasizes the pros and cons of phytoestrogens on human health, which may help to direct the pharmaceutical industry to produce various phytoestrongen based drugs against various metabolic disorders.

scholarly journals Tracking late Pleistocene Neandertals on the Iberian coast

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Eduardo Mayoral ◽  
Ignacio Díaz-Martínez ◽  
Jéremy Duveau ◽  
Ana Santos ◽  
Antonio Rodríguez Ramírez ◽  
...  
Keyword(s):  
High Resolution ◽  
Iberian Peninsula ◽  
Social Group ◽  
Microbial Mats ◽  
3D Models ◽  
Age Classes ◽  
Upper Pleistocene ◽  
Wide Range ◽  
The World ◽  
Flooded Area

AbstractHere, we report the recent discovery of 87 Neandertal footprints on the Southwest of the Iberian Peninsula (Doñana shoreline, Spain) located on an upper Pleistocene aeolian littoral setting (about 106 ± 19 kyr). Morphometric comparisons, high resolution digital photogrammetric 3D models and detailed sedimentary analysis have been provided to characterized the footprints and the palaeoenvironment. The footprints were impressed in the shoreline of a hypersaline swamped area related to benthic microbial mats, close to the coastline. They have a rounded heel, a longitudinal arch, relatively short toes, and adducted hallux, and represent the oldest upper Pleistocene record of Neandertal footprints in the world. Among these 87 footprints, 31 are longitudinally complete and measure from 14 to 29 cm. The calculated statures range from 104 to 188 cm, with half of the data between 130 and 150 cm. The wide range of sizes of the footprints suggests the existence of a social group integrated by individuals of different age classes but dominated, however, by non-adult individuals. The footprints, which are outside the flooded area are oriented perpendicular to the shoreline. These 87 footprints reinforce the ecological scenario of Neandertal groups established in coastal areas.

scholarly journals Age of maturation and behavioral tactics in male yellow ground squirrel Spermophilus fulvus during mating season

2014 ◽  
Vol 60 (6) ◽  
pp. 700-711 ◽  
Author(s):  
Nina A. Vasilieva ◽  
Ekaterina V. Pavlova ◽  
Sergey V. Naidenko ◽  
Andrey V. Tchabovsky
Keyword(s):  
Body Size ◽  
Ground Squirrel ◽  
Life History Theory ◽  
Social Activity ◽  
Indirect Evidence ◽  
Adult Size ◽  
Adult Males ◽  
Mating Season ◽  
Active Season ◽  
Good Physical Condition

Abstract Life-history theory predicts that in hibernators age of maturation is related positively to body size and negatively to the duration of active season aboveground. Yellow souslik is a large-sized ground squirrel with long hibernation, which suggests late maturation. We used four-year field observations of marked individuals to determine the age of maturation in males through analysis of age-dependent variation in body size, mass, androgen status, timing of spring emergence, ranging patterns and social behavior during the mating season. Yearling males were smaller, lighter, had lower level of fecal testosterone, emerged later and had smaller home ranges than older males. Social activity and the number of females encountered did not differ between age classes. After the second hibernation none of the studied parameters varied with age. Cluster analysis revealed two behavioral tactics: “active” males (adults only) emerged earlier, ranged more widely, initiated more contacts, encountered more females and were heavier than “passive” males (both yearling and adult). Thus, males of S. fulvus reached adult size and matured after two hibernations, which is relatively fast for such a big species with short active period. Indirect evidence for copulations and high variation among yearlings in all parameters suggest that some of them might successfully compete with adults. Active tactic of wandering and searching for females is energetically costly, and probably only adult males in good physical condition can afford it, whereas passive tactic of residing is energy saving and good for adults in poor condition and for yearlings that are continuing to grow.

The influence of underwater data transmission sounds on the displacement behaviour of captive harbour seals (Phoca vitulina)

2006 ◽  
Vol 61 (1) ◽  
pp. 19-39 ◽  
Author(s):  
Ronald A. Kastelein ◽  
Sander van der Heul ◽  
Willem C. Verboom ◽  
Rob J.V. Triesscheijn ◽  
Nancy V. Jennings
Keyword(s):  
Data Transmission ◽  
Phoca Vitulina ◽  
Harbour Seals
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