Pup development and timing of pupping in harbour seals (Phoca vitulina) in the St. Lawrence River estuary, Canada

2003 ◽  
Vol 81 (2) ◽  
pp. 188-194 ◽  
Author(s):  
Y Dubé ◽  
M O Hammill ◽  
C Barrette
Keyword(s):  
River Estuary ◽  
Phoca Vitulina ◽  
Daily Growth Rate ◽  
Daily Growth ◽  
Harbour Seals ◽  
Pup Development ◽  
Lactation Duration ◽  
Relationship Of ◽  
The Relationship ◽  
St Lawrence River

Surveys to estimate the daily growth rate of harbour seal (Phoca vitulina) pups from birth to weaning and to determine the distribution of births were carried out from early May to late August 1998, 1999, and 2000 at two haulout areas in the St. Lawrence River estuary, Canada. Pups gained mass at a rate of 0.544 kg/day (standard error (SE) = 0.141, range 0.118–0.875 kg/day, N = 110). Births began between 12 and 17 May. The median dates of birth were 28 May (95% confidence interval (CI), 27–30 May) in 1998, 25 May (95% CI, 24–28 May) in 1999, and 26 May (95% CI, 24–27 May) in 2000. Births followed a normal distribution in 2000, but late pupping led to an extended tail in both 1998 and 1999. Pupping occurred at the same time in the St. Lawrence River estuary as at Sable Island, a colony located 600 km to the south, but occurred earlier than predicted by the relationship of Temte et al. (1991). The estimated median dates of weaning were 1 July (95% CI, 20 June to 12 July) in 1998, 30 June (95% CI, 19 June to 11 July) in 1999, and 26 June (95% CI, 20 June to 2 July) in 2000. Pooling years resulted in an average lactation duration of 34 days (SE = 1.8).

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.

Mother-Young Interactions in the Common Seal, Phoca Vitulina Vitulina

Behaviour ◽  
1974 ◽  
Vol 48 (1-4) ◽  
pp. 23-35 ◽  
Author(s):  
Susan Wilson
Keyword(s):  
Close Contact ◽  
Phoca Vitulina ◽  
Suckling Period ◽  
Considerable Distance ◽  
Strangford Lough ◽  
Characteristic Behaviour ◽  
The Common ◽  
Relationship Of ◽  
The Relationship

AbstractThe mother-young relationship of the common seal Phoca vitulina in Strangford Lough, N.E. Ireland, lasted about three weeks. Mothers with young were most active during the first two hours of the ebb, and also they spent more time in the water when the ebb occurred towards evening than in the morning. Characteristic behaviour in the water included (i) the mother guiding the pup and maintaining close contact with it (ii) playing, and (iii) the pup sleeping at the surface with the mother close by. Progressive changes in the relationship included a slight decrease in time spent by the mother in guiding the pup, a slight increase in time spent close together, an increase in time spent at a considerable distance apart, and an increase in time spent by the pup sleeping at the surface. Throughout the suckling period the mother controlled the onset of suckling, but rarely terminated it. Throughout, also, the pup broke contact the most, while the mother re-established contact the most. Just before weaning, mothers left their pups for long periods, the separation sometimes terminating a play bout.

The effect of weather conditions on harbour seal (Phoca vitulina) haulout behaviour in the Moray Firth, northeast Scotland

1996 ◽  
Vol 74 (10) ◽  
pp. 1806-1811 ◽  
Author(s):  
Kate Grellier ◽  
Paul M. Thompson ◽  
Heather M. Corpe
Keyword(s):  
Significant Relationship ◽  
Seasonal Changes ◽  
Negative Relationship ◽  
Weather Conditions ◽  
Phoca Vitulina ◽  
Effect Of Temperature ◽  
Harbour Seals ◽  
Moray Firth ◽  
A Site ◽  
The Relationship

Abundance data from a 6-year study (1988–1993) of harbour seals (Phoca vitulina) were used to control for seasonal changes in haulout behaviour and assess the effect of temperature and other weather conditions on haulout numbers at a site in Scotland. A significant relationship between Julian day and haulout numbers was consistent between years. In some years, there was also a significant relationship between ambient temperature and haulout numbers, but examination of the residuals around the relationship between haulout numbers and Julian day revealed no evidence for a consistent effect of temperature, wind speed, or wind-chill adjusted temperatures. A weak negative relationship between haulout numbers and both precipitation and cloud cover did exist, but these variables explained little of the variation in seal numbers.

The relationship of thyroxine and cortisol to the moult of the harbor seal Phoca vitulina

1977 ◽  
Vol 31 (4) ◽  
pp. 398-401 ◽  
Author(s):  
J.Edmond Riviere ◽  
F.Rainer Engelhardt ◽  
Jolane Solomon
Keyword(s):  
Harbor Seal ◽  
Phoca Vitulina ◽  
Relationship Of ◽  
The Relationship

scholarly journals Bahan Organik Total dan Kelimpahan Bakteri di Perairan Teluk Benoa, Bali

2017 ◽  
Vol 4 (1) ◽  
pp. 129 ◽  
Author(s):  
Ni Luh Eta Yuspita ◽  
I Dewa Nyoman Nurweda Putra ◽  
Yulianto Suteja
Keyword(s):  
Organic Matter ◽  
Bacterial Abundance ◽  
Total Concentration ◽  
River Estuary ◽  
Temporal Distribution ◽  
Plate Count ◽  
Total Plate Count ◽  
Net Cage ◽  
Relationship Of ◽  
The Relationship

Benoa Bay is semi-enclosed waters that have various activities. The existence of these activities will contribute to organic matter in the waters so that the effect on the presence of bacteria. This study aims to determine the total concentration of total organic matter (TOM) and bacterial abundance as well as its spatial and temporal distribution, and to determine the relationship of TOM concentration to bacterial abundance in the waters of Benoa Bay. Data collection is conducted on the surface of the waters in December 2016 to February 2017 when ebb conditions at 5 Benoa Bay water stations. Measurement of organic matter using permanganate test in titimetry based on standard methods SNI 06-6989.22-2004. Measurement of bacterial abundance using Total Plate Count (TPC) method. The TOM concentrations ranged from 63.20 to 65.10 mg/l and bacterial abundances ranged from 30 to 300 CFU/ml. Spatial distribution of TOM concentration and bacterial abundance tends to be higher close to Suwung Landfills (TPA) activity, floating net cage cultivation (KJA) activity in Serangan waters, and Buaji river estuary and tend to be lower approaching Benoa harbor activity and waters further from those activities. The concentration of TOM and bacterial abundance in December 2016 to February 2017 have fluctuating values. Based on the interpretation of the correlation coefficient, the level of relationship between BOT concentration and bacterial abundance in the waters of Benoa Bay is quite strong.

scholarly journals Factors influencing the economics of the pork meat production

2011 ◽  
Vol 57 (No. 4) ◽  
pp. 203-209 ◽  
Author(s):  
J. Babović ◽  
M. Carić ◽  
D. Djordjević ◽  
S. Lazić
Keyword(s):  
Labour Productivity ◽  
Live Weight ◽  
Economic Effects ◽  
Risk Level ◽  
Meat Production ◽  
Pork Meat ◽  
Daily Growth ◽  
Feed Costs ◽  
Relationship Of ◽  
The Relationship

The research of the influence of the relevant factors and their interrelations on the economics of the pork meat production on a farm has been carried out with the help of the method of production functions (factor &ndash; product and factor &ndash; factor). The influence of the weight of an animal on the daily growth tells us that the growth is increased with the increase of the entry weight to 19 kg and with the exit weight of the fattened animal of 100 kg . The growth is decreased over these weights. The relationship between the daily growth and the feed costs by a feeding day shows us the tendency of the increase of a daily growth with the increase of the feed costs. With the increase of labour inputs to 2.6 hours/100 kg of the live weight and the increased profit to 29 monetary units, first, the daily growth is decreased, and, then, it begins to grow. Labour productivity grows with the increase of the capacity usage to 87%, and, then, it decreases. The influence of the feedlot capacity usage on the productivity measured by the correlation coefficient is 0.756 at the risk level of 1%. With the increase of the feedlot capacity usage, the economics of production is increased and the cost price is decreased. The economics of the production of pork meat is increased with a decreasing rate with the increase of the daily growth. The manifold influence of the examined factors on the economics movement is low (R = &ndash;0.355). The partial influence of the costs to the economy is 90.3% that of the direct costs is 80.3%, from which the feed costs have an influence of 51.7%. The influence of the indirect costs on the economics is low, but with their increase, the economics is decreased. It has been noticed that the economics changes can be explained with 66.8% by the change of the relationship of the selling and purchasing price of pigs and the purchasing price of feed concentrate. By the relationship of the price of the fattened animals and the feed concentrate lower than 1 : 5, the economic result is below 1, and above the previously mentioned parity, the economics is increased as well as the economic effects of production.

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.

scholarly journals Relation Dynamic Shear Stress and Wake Boat Waves Energy

2020 ◽  
Vol 8 (6) ◽  
pp. 2558-2564
Keyword(s):  
Shear Stress ◽  
Wave Height ◽  
Tidal Flow ◽  
River Estuary ◽  
Peninsular Malaysia ◽  
Local State ◽  
Dynamic Shear ◽  
Recreational Vessels ◽  
Relationship Of ◽  
The Relationship

Coastal area is the most populated throughout the world due to its business activities especially those involves commercial or recreational vessels to bring people or goods. Inadvertently, heavily vessels traffic will create effect on shoreline, riverbank or estuaries in which resulting an erosion problem. Overcoming the problem, a few local state authorities are enforcing a regulation for the vessels to cruise along the coastline to minimize the erosion impact. This research was conducted to study the relationship of dynamic shear stress generated from wake boat and tidal flow induced energy at Kemaman river estuary, which located at Kemaman province, East Coast of Peninsular Malaysia. Evidence shows that erosion occurred along the riverbank, and it was confirmed that the vessels contribute to the erosion problem due to negligence of vessels’ speed. In addition, apart from the generated energy coming from the vessel, the dimension of the vessels also contributes to the erosion problem. The estimation of total energy created by each vessel is established by a formula through the relationship with wave energy under influenced of maximum wave height. The results indicate that increases in energy will increase the dynamic shear stress due to orbital wave velocity whereby it is a function of wave height generated by boat wave. Finally, the results also indicate addition minimum tidal flow rate and wake boat contributes higher dynamic shear stress as compared to mud bed shear stress. Therefore, it can be concluded that wake boat waves play a significant role in determining the riverbank erosion. The finding of this study serves some information as guidance to local state authority to impose regulation to community whom using the vessels to navigate through this estuary.

The relationship of the increased level of metallothionein with heavy metal levels in the tissue of the harbor seal (Phoca vitulina)

1986 ◽  
Vol 12 (1) ◽  
pp. 85-94 ◽  
Author(s):  
Chiharu Tohyama ◽  
Sei-Ichiro Himeno ◽  
Chiho Watanabe ◽  
Tsuguyoshi Suzuki ◽  
Masatoshi Morita
Keyword(s):  
Heavy Metal ◽  
Harbor Seal ◽  
Phoca Vitulina ◽  
Metal Levels ◽  
Relationship Of ◽  
The Relationship
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