Regulation compliance by vessels and disturbance of harbour seals (Phoca vitulina)

2007 ◽  
Vol 85 (2) ◽  
pp. 290-294 ◽  
Author(s):  
Amber Johnson ◽  
Alejandro Acevedo-Gutiérrez
Keyword(s):  
Marine Mammals ◽  
Buffer Zone ◽  
Geographic Area ◽  
Phoca Vitulina ◽  
Harbor Seals ◽  
Buffer Zones ◽  
Harbour Seals ◽  
The Us ◽  
Regulation Compliance

The US National Oceanic and Atmospheric Administration established a buffer zone around marine mammals to prevent harassment. The buffer zone varies by species listing status and by geographic area. However, it is unknown the extent to which vessels comply with these buffer zones. We selected harbor seals ( Phoca vitulina L., 1758) as a case study to describe compliance with the buffer zone. We conducted land-based observations from Yellow Island, Washington State, in a geographic area where the buffer zone is 91 m (100 yards), to estimate vessel distance from hauled-out seals and to evaluate seal response. We recorded 85.7% of kayaks, 57.1% of stopped powerboats, and 4.6% of passing powerboats violating the buffer zone. Seals were disturbed by kayaks and stopped powerboats at distances >91 m from the haul-out sites but not by moving powerboats ≤91 m from the sites. Hence, compliance of the buffer zone varied with vessel type and vessel activity. We suggest that a larger buffer zone for vessels lingering around the haul-out sites and enforcement of the buffer zone will minimize seal disturbance.

scholarly journals Transnational productions of remoteness: building onshore and offshore carceral regimes across borders

2014 ◽  
Vol 69 (5) ◽  
pp. 389-398 ◽  
Author(s):  
A. Mountz ◽  
J. Loyd
Keyword(s):  
Buffer Zone ◽  
The United States ◽  
Political Debate ◽  
The Us ◽  
History Of ◽  
The Caribbean ◽  
Us Federal Government ◽  
The Relationship ◽  
Cold War History

Abstract. This article examines transnational framings of domestic carceral landscapes to better understand the relationship between offshore and onshore enforcement and detention regimes. US detention on mainland territory and interception and detention in the Caribbean serves as a case study. While the US domestic carceral regime is a subject of intense political debate, research, and activism, it is not often analyzed in relation to the development and expansion of an offshore "buffer zone" to intercept and detain migrants and asylum seekers. Yet the US federal government has also used offshore interception and detention as a way of controlling migration and mobility to its shores. This article traces a Cold War history of offshore US interception and detention of migrants from and in the Caribbean. We discuss how racialized crises related to Cuban and Haitian migrations by sea led to the expansion of an intertwined offshore and onshore carceral regime. Tracing these carceral geographies offers a more transnational understanding of contemporary domestic landscapes of detention of foreign nationals in the United States. It advances the argument that the conditions of remoteness ascribed frequently to US detention sites must be understood in more transnational perspective.

scholarly journals Treatment of naturally acquired demodectic mange with amitraz in two harbour seals (Phoca vitulina)

2015 ◽  
Vol 63 (3) ◽  
pp. 352-357 ◽  
Author(s):  
Kyoo-Tae Kim ◽  
Seung-Hun Lee ◽  
Dongmi Kwak
Keyword(s):  
Successful Treatment ◽  
Marine Mammals ◽  
Clinical Signs ◽  
Skin Lesions ◽  
Phoca Vitulina ◽  
Aetiological Agent ◽  
Harbour Seals ◽  
Causative Agents ◽  
Pure Cultures

Two male harbour seals (Phoca vitulina; 33 and 35 years old, respectively), housed since 2002 at a zoo for exhibition purposes, developed severe, multifocal and diffuse skin lesions. Skin scrapings and microscopy for parasites as well as pure cultures for bacteria and dermatophytes were carried out to identify the aetiological agent. Skin scrapings showed that lesions appearing on the seals were caused by an infestation of Demodex mites, which is uncommon in marine mammals, and were not due to other causative agents (parasites, bacteria or dermatophytes). Treatment with amitraz (0.01%) once a week for three weeks and with ampicillin (10 mg/kg SID per os) for six days eliminated the mites and resolved the clinical signs of demodectic mange in the harbour seals. The purpose of this report is to describe the successful treatment of naturally acquired demodectic mange with amitraz in harbour seals.

Genetic analysis of Washington State harbor seals (Phoca vitulina richardii) using microsatellites

2012 ◽  
Vol 90 (12) ◽  
pp. 1361-1369 ◽  
Author(s):  
H.R. Huber ◽  
B.R. Dickerson ◽  
S.J. Jeffries ◽  
D.M. Lambourn
Keyword(s):  
Nuclear Dna ◽  
Puget Sound ◽  
Phoca Vitulina ◽  
Washington State ◽  
Inland Waters ◽  
Harbor Seals ◽  
Hood Canal ◽  
The Us ◽  
Males And Females ◽  
Phoca Vitulina Richardii

Washington harbor seals ( Phoca vitulina richardii (Gray, 1864)) are currently managed as two stocks: Washington Coastal Stock and Washington Inland Waters Stock. Previous analysis of mitochondrial DNA (mtDNA) in Washington harbor seals showed four geographically and genetically distinct populations. In this study of biparentally inherited nuclear DNA, we analyzed nine microsatellite loci on 482 samples of unweaned pups from nine locations in Washington State and the US–Canadian transboundary waters to determine if there were differences in gene flow between males and females. We found the same four genetically and geographically distinct populations as the analysis of maternally inherited mtDNA: Washington Coast, north Inland Waters, Hood Canal, and south Puget Sound. We recommend that the coastal stock remain as is, but the harbor seals in the Washington Inland Waters should be managed as three distinct populations rather than one.

Transit time of digesta in captive harbour seals (Phoca vitulina)

1993 ◽  
Vol 71 (5) ◽  
pp. 1071-1073 ◽  
Author(s):  
Nina Hedlund Markussen
Keyword(s):  
Transit Time ◽  
Marine Mammals ◽  
Barium Sulphate ◽  
Stomach Content Analysis ◽  
Phoca Vitulina ◽  
Caloric Content ◽  
X Rays ◽  
Qualitative And Quantitative ◽  
Harbour Seals ◽  
Time Required

Stomach-content analysis can be used to identify the species and size of prey fishes eaten by marine mammals, and has been used for both qualitative and quantitative estimates of their food requirements. Methods that use mass or volume to determine the amount of fish eaten depend on the degree of digestion and the time required for the stomach to empty. The transit time of digesta was estimated by recording the initial defecation time and the time required for the stomach to empty in four harbour seals (Phoca vitulina). The seals were given meals varying in size from 0.5 to 2.1 kg and in caloric content from 4940 to 12 770 kJ/kg, and containing carmine or barium sulphate as a marker. The time from eating until red faeces were observed was between 2 h 35 min and 6 h 15 min. Also, barium sulphate was injected into the food given, and X-rays were used to estimate the time required for the stomach to empty. The stomach started to empty less than 1 h after the meal. Some prey remained in the stomach 5 h after eating.

scholarly journals Laryngeal and soft palate valving in the harbour seal (Phoca vitulina)

2020 ◽  
Vol 223 (20) ◽  
pp. jeb230201
Author(s):  
Arlo Adams ◽  
Wayne Vogl ◽  
Camilla Dawson ◽  
Stephen Raverty ◽  
Martin Haulena ◽  
...  
Keyword(s):  
Soft Palate ◽  
Marine Mammals ◽  
Vocal Folds ◽  
Phoca Vitulina ◽  
Harbour Seal ◽  
Upper Aerodigestive Tract ◽  
Laryngeal Inlet ◽  
Harbour Seals ◽  
Lateral Margins ◽  
And Function

ABSTRACTEffective ‘valving’ in the upper aerodigestive tract (UAT) is essential to temporarily separate the digestive and respiratory pathways. Marine mammals are largely dedicated to feeding underwater, and in many cases swallowing prey whole. In seals, little work has been done to explore the anatomy and function of the UAT in the context of valving mechanisms that function to separate food and air pathways. Here we use videofluoroscopy, gross dissection, histology and computed tomography (CT) renderings to explore the anatomy of the larynx and soft palate in the harbour seal (Phoca vitulina), and generate models for how valving mechanisms in the head and neck may function during breathing, phonating, diving and swallowing. Harbour seals have an elevated larynx and the epiglottis may rise above the level of the soft palate, particularly in pups when sucking. In addition, the corniculate and arytenoid cartilages with associated muscles form most of the lateral margins of the laryngeal inlet and vestibule, and move independently to facilitate airway closure. The corniculate cartilages flex over the laryngeal inlet beneath the epiglottis to completely close the laryngeal vestibule and inlet. The vocal folds are thick and muscular and the medial margin of the folds contains a small vocal ligament. The soft palate has well-defined levator veli palatini muscles that probably function to elevate the palate and close the pharyngeal isthmus during feeding. Our results support the conclusion that harbour seals have evolved UAT valving mechanisms as adaptations to a marine environment that are not seen in terrestrial carnivores.

scholarly journals Metagenomic identification of a novel anellovirus in Pacific harbor seal (Phoca vitulina richardsii) lung samples and its detection in samples from multiple years

2011 ◽  
Vol 92 (6) ◽  
pp. 1318-1323 ◽  
Author(s):  
Terry Fei Fan Ng ◽  
Elizabeth Wheeler ◽  
Denise Greig ◽  
Thomas B. Waltzek ◽  
Frances Gulland ◽  
...  
Keyword(s):  
Marine Mammals ◽  
Harbor Seal ◽  
Phoca Vitulina ◽  
Viral Metagenomics ◽  
Harbor Seals ◽  
California Sea Lions ◽  
Viral Pathogens ◽  
Sea Lions ◽  
Mortality Event ◽  
Specific Pcr

To investigate viral pathogens potentially involved in a mortality event of 21 Pacific harbor seals (Phoca vitulina richardsii) in California in 2000, viral metagenomics was performed directly on lung samples from five individuals. Metagenomics revealed a novel seal anellovirus (SealAV), which clusters phylogenetically with anelloviruses from California sea lions and domestic cats. Using specific PCR, SealAV was identified in lung tissue from two of five animals involved in the 2000 mortality event, as well as one of 20 harbor seal samples examined post-mortem in 2008. The identification of SealAV in multiple years demonstrates that this virus is persistent in the harbor seal population. SealAV is the second anellovirus reported in the lungs of pinnipeds, suggesting that anellovirus infections may be common amongst marine mammals and that more research is needed to understand the roles of these viruses in marine mammal health and disease.

scholarly journals Arsenic speciation in bodily fluids of harbor seals (Phoca vitulina) and harbor porpoises (Phocoena phocoena)

2009 ◽  
Vol 6 (4) ◽  
pp. 319 ◽  
Author(s):  
Linda Kuenstl ◽  
Simone Griesel ◽  
Andreas Prange ◽  
Walter Goessler
Keyword(s):  
Marine Mammals ◽  
Feeding Habits ◽  
Arsenic Speciation ◽  
Phoca Vitulina ◽  
Dimethylarsinic Acid ◽  
Harbor Seals ◽  
Phocoena Phocoena ◽  
Bodily Fluids ◽  
The North ◽  
Harbor Porpoises

Environmental context. Marine mammals play an important role in their ecosystem. As top predators they ingest a lot of arsenic from their food. In the present study bodily fluids and tissue samples of harbor seals and porpoises were investigated for arsenic speciation in order to obtain a clearer picture on their feeding habits and consequently a better understanding of the mass mortality of the animals in the North and Baltic Sea. Abstract. The total arsenic concentrations and arsenic speciation in various tissues and bodily fluids of harbor seals (Phoca vitulina) and harbor porpoises (Phocoena phocoena) were determined to obtain information about the feeding habits of these endangered marine mammals. Lower whole blood arsenic concentrations were found for fish-fed (median: 71 μg As L–1) than for free ranging seals (median: 190 μg As L–1). In porpoise liver the arsenic concentrations were higher from carcasses found in the North Sea (median: 421 μg As kg–1 wet mass) than from those inhabiting the Baltic Sea or found in the River Elbe (median: 250 μg As kg–1). The arsenic speciation in the urine, plasma, and gastric juice of seals and the urine of porpoises, collected from animals at different areas in the North and Baltic Seas, revealed the following picture: arsenobetaine was the predominant arsenic species in all measured bodily fluids. Plasma samples of seals contained only dimethylarsinic acid as additional species. In gastric juice arsenocholine and trimethylarsine oxide were found at trace concentrations. Several arsenic compounds were identified in mammals’ urine, the major being dimethylarsinic acid and thio-dimethylarsinic acid but high variability was observed in the relative proportions of each. No correlation between degree of decay and arsenic speciation in urine could be found. This is very useful information as older carcasses can also be included in future studies. Our preliminary results are promising to obtain an insight into feeding habits of seals and porpoises by the arsenic speciation in urine.

scholarly journals Age determination methods in harbour seals (Phoca vitulina) with a review of methods applicable to carnivores

2010 ◽  
Vol 8 ◽  
pp. 245 ◽  
Author(s):  
Christina Lockyer ◽  
Beth Mackey ◽  
Fiona Read ◽  
Tero Härkönen ◽  
Ilk Hasselmeier
Keyword(s):  
Best Practices ◽  
Marine Mammals ◽  
Tooth Extraction ◽  
Age Determination ◽  
Detailed Examination ◽  
Phoca Vitulina ◽  
Growth Layer ◽  
Harbour Seals ◽  
Determination Methods ◽  
Layer Groups

The development of age determination methods in marine mammals is reviewed with particular reference to the use of teeth Growth Layer Groups (GLGs) formed in the dentine and cement of carnivores. Using this background, practices for sampling, tooth extraction and collection, storage and different methods of preparation of teeth as well as reading and counting GLGs are discussed and evaluated for the harbour seal (Phoca vitulina). The paper includes comments on best practices for counting GLGs with new examples from known-age seals, and also a detailed examination of confounding factors in interpreting GLGs such as mineralization anomalies and the phenomena of accessory lines, “false annuli” and “paired laminae” which have not been discussed previously. The paper concludes with recommendations for undertaking age estimation in harbour seals from sampling through final GLG interpretation with special emphasis on standardization of methods with other researchers.

scholarly journals Tooth Microwear Texture in the Eastern Atlantic Harbour Seals (Phoca vitulina vitulina) of the German Wadden Sea and Its Implications for Long Term Dietary and Ecosystem Changes

2021 ◽  
Vol 9 ◽  
Author(s):  
Elehna Bethune ◽  
Ellen Schulz-Kornas ◽  
Kristina Lehnert ◽  
Ursula Siebert ◽  
Thomas M. Kaiser
Keyword(s):  
Health Status ◽  
Marine Mammal ◽  
Marine Mammals ◽  
Wadden Sea ◽  
Anthropogenic Impacts ◽  
Phoca Vitulina ◽  
Dental Microwear ◽  
Future Health ◽  
Terrestrial Mammals ◽  
Harbour Seals

Marine mammals are increasingly threatened in their habitat by various anthropogenic impacts. This is particularly evident in prey abundance. Understanding the dietary strategies of marine mammal populations can help predict implications for their future health status and is essential for their conservation. In this study we provide a striking example of a new dietary proxy in pinnipeds to document marine mammal diets using a dental record. In this novel approach, we used a combination of 49 parameters to establish a dental microwear texture (DMTA) as a dietary proxy of feeding behaviour in harbour seals. This method is an established approach to assess diets in terrestrial mammals, but has not yet been applied to pinnipeds. Our aim was to establish a protocol, opening DMTA to pinnipeds by investigating inter- and intra-individual variations. We analysed the 244 upper teeth of 78 Atlantic harbour seals (Phoca vitulina vitulina). The specimens were collected in 1988 along the North Sea coast (Wadden Sea, Germany) and are curated by the Zoological Institute of Kiel University, Germany. An increasing surface texture roughness from frontal to distal teeth was found and related to different prey processing biomechanics. Ten and five year old individuals were similar in their texture roughness, whereas males and females were similar to each other with the exception of their frontal dentition. Fall and summer specimens also featured no difference in texture roughness. We established the second to fourth postcanine teeth as reference tooth positions, as those were unaffected by age, sex, season, or intra-individual variation. In summary, applying indirect dietary proxies, such as DMTA, will allow reconstructing dietary traits of pinnipeds using existing skeletal collection material. Combining DMTA with time series analyses is a very promising approach to track health status in pinniped populations over the last decades. This approach opens new research avenues and could help detect dietary shifts in marine environments in the past and the future.

Does Enrichment Improve Well Being in Animals under Human Care? A Case Study of Two Harbor Seals (Phoca Vitulina)

2018 ◽  
Vol 22 (3) ◽  
pp. 255-266 ◽  
Author(s):  
Ruta Vaicekauskaite ◽  
Jennifer N. Schneider ◽  
Fabienne Delfour
Keyword(s):  
Well Being ◽  
Phoca Vitulina ◽  
Harbor Seals ◽  
Human Care
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