Impact Of Colonial Sealing On Seal Stocks Around Australia, New Zealand And Subantarctic Islands Between 150 And 170 Degrees East

2002 ◽  
Vol 24 (1) ◽  
pp. 117 ◽  
Author(s):  
JK Ling

Details of southern elephant seal oil and fur seal and sea lion skin cargoes have been extracted from a large number of secondary sources dealing with Australian and New Zealand maritime history, which in turn referred to numerous primary sources of information. The data were collated and analysed for ten areas in the south-west Pacific region and published recently in two separate larger works. This review is a synthesis and analysis of the impact of the colonial sealing industry on seal stocks in the region, based on those papers, with some minor revisions and reference to works by other authors. Colonial sealing lasted from the late 18th to the mid- 19th century and was followed by sporadic hunting until the late 1940s. Southern elephant seals (Mirounga leonina) were hunted for their oil; and Australian fur seals (Arctocephalus pusillus doriferus), New Zealand fur seals (Arctocephalus forsteri), Australian sea lions (Neophoca cinerea) and New Zealand sea lions (Phocarctos hookeri) were targeted for their skins and some oil. At least 1,081 tons of elephant seal oil were shipped from King Is. between 1802 and 1819, while 8,380 tons were shipped from Macquarie Is. between 1810 and 1919. More than 1.4 million skins of both species of fur seals were harvested between 1792 and 1949, but only 4,000 Neophoca and 5,700 Phocarctos pelts are recorded as having been shipped by 1840. The Antipodes Islands yielded more than a quarter of the total fur seal skin harvest, and New Zealand and southern Australia each delivered a quarter of the total. Current numbers of the two species of fur seals combined are about a tenth of the crudely estimated size (1.5 million) of the original population. The exploited fur seals and sea lions were probably the same species as occur today at the original sealing localities, apart from Macquarie Is. where the identity of the exploited fur seals remains in doubt. There is some evidence that Maoris and Australian Aborigines hunted seals in pre-European times, resulting in reduced ranges and depleted stocks that were exploited later by colonial sealers.

2008 ◽  
Vol 20 (5) ◽  
pp. 425-435 ◽  
Author(s):  
Donald B. Siniff ◽  
Robert A. Garrott ◽  
Jay J. Rotella ◽  
William R. Fraser ◽  
David G. Ainley

AbstractWe consider how Antarctic seals may respond to changes in climate, realizing that anthropogenic alteration of food webs will influence these responses. The species considered include the ice-obligate - crabeater (Lobodon carcinophaga), Weddell (Leptonychotes weddellii), Ross (Ommataphoca rossii) and leopard (Hydrurga leptonyx) seal - and the ice-tolerant Antarctic fur seal (Arctocephalus gazella) and southern elephant seal (Mirounga leonina). The data analysed are from long-term censuses of Weddell seals in McMurdo Sound (1997–2006), and of Weddell, fur and elephant seals at Arthur Harbour, Antarctic Peninsula (1974–2005). After considering their responses to recent changes in environmental features, as well as projected and current changes to their habitat our conclusions are that the distribution and abundance of 1) crabeater and Weddell seals will be negatively affected by changes in the extent, persistence and type of annual sea ice, 2) Ross and leopard seal will be the least negatively influenced by changes in pack ice characteristics, although, as may be the case for crabeater and Weddell, population size and distribution may be altered through changes in food web dynamics, and 3) southern elephant and fur seals will respond in ways opposite to the pack ice species, but could also be influenced most immediately by changes in their food resources due to factors other than climate.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Natália Procksch ◽  
M. Florencia Grandi ◽  
Paulo Henrique Ott ◽  
Karina Groch ◽  
Paulo A. C. Flores ◽  
...  

AbstractWe present estimates of the seasonal and spatial occupation by pinnipeds of the Wildlife Refuge of Ilha dos Lobos (WRIL), based on aerial photographic censuses. Twenty aerial photographic censuses were analysed between July 2010 and November 2018. To assess monthly differences in the numbers of pinnipeds in the WRIL we used a Generalized Linear Mixed Model. Spatial analysis was carried out using Kernel density analysis of the pinnipeds on a grid plotted along the WRIL. Subadult male South American sea lions (Otaria flavescens) were the most abundant pinniped in the WRIL. Potential females of this species were also recorded during half of the census. The maximum number of pinnipeds observed in the WRIL was 304 in September 2018, including an unexpected individual southern elephant seal (Mirounga leonina), and a high number of South American fur seal yearlings (Arctocephalus australis). However, there was no statistically significant difference in counts between months. In all months analysed, pinnipeds were most often found concentrated in the northern portion of the island, with the highest abundances reported in September. This study confirms the importance of the WRIL as a haulout site for pinnipeds in Brazil, recommends that land research and recreational activities occur in months when no pinnipeds are present, and encourages a regulated marine mammal-based tourism during winter and spring months.


2002 ◽  
Vol 24 (1) ◽  
pp. 85 ◽  
Author(s):  
LJ Boren ◽  
NJ Gemmell ◽  
KJ Barton

Marine mammals are significant tourist attractions around New Zealand, however, the impact of eco-tourism on these species is poorly documented. Effective management to mitigate any negative effects requires an understanding of target species? reactions to tourist activities. We have studied the effects of tourist activities on New Zealand fur seals (Arctocephalus forsteri) using a novel combination of observations and controlled approaches. Three study areas were selected reflecting a range of visitor density, type of tourism, and the anticipated sensitivity of fur seals to disturbance. Behaviour was observed using instantaneous scan sampling and attributes of tourist approaches were tested experimentally by controlled approaches. Approaches were made on land, by kayak, and motorboat. Fur seal responses and the distance at which the seal responded were recorded. Our results indicate that A. forsteri behaviour was being modified by tourist activities. Habituation was occurring at study areas with high levels of tourist activity. Approachers following current minimum approach distances still caused some animals to modify their behaviour and new minimum approach distances are recommended based on controlled approaches to seals at all study areas. Our work demonstrated that controlled approaches can be a useful tool to develop effective management guidelines to lessen impacts from eco-tourism activities.


2010 ◽  
Vol 58 (2) ◽  
pp. 94 ◽  
Author(s):  
Peter D. Shaughnessy ◽  
Jane McKenzie ◽  
Melanie L. Lancaster ◽  
Simon D. Goldsworthy ◽  
Terry E. Dennis

Australian fur seals (Arctocephalus pusillus doriferus) breed on Bass Strait islands in Victoria and Tasmania. They have been recorded in South Australia (SA) for many years as non-breeding visitors and on Kangaroo Island frequently since 1988, mostly in breeding colonies of the New Zealand fur seal (A. forsteri) which is the most numerous pinniped in SA. Australian fur seals have displaced New Zealand fur seals from sections of the Cape Gantheaume colony on Kangaroo Island. North Casuarina Island produced 29 Australian fur seal pups in February 2008. Australian fur seal pups were larger than New Zealand fur seal pups in the same colony and have been identified genetically using a 263-bp fragment of the mitochondrial DNA control region. North Casuarina Island has been an important breeding colony of New Zealand fur seals, but pup numbers there decreased since 1992–93 (contrary to trends in SA for New Zealand fur seals), while numbers of Australian fur seals there have increased. This study confirms that Australian fur seals breed in SA. The two fur seal species compete for space onshore at several sites. Australian fur seals may compete for food with endangered Australian sea lions (Neophoca cinerea) because both are bottom feeders.


2005 ◽  
Vol 32 (1) ◽  
pp. 85 ◽  
Author(s):  
P. D. Shaughnessy ◽  
T. E. Dennis ◽  
P. G. Seager

Two seal species breed on the west coast of South Australia, the Australian sea lion, Neophoca cinerea, and the New Zealand fur seal, Arctocephalus forsteri. Aerial surveys were conducted at intervals of ~3 months between April 1995 and June 1997 to determine the breeding status of sea lions and timing of pupping seasons. Ground surveys between October 1994 and April 2004 aimed at counting sea lions and fur seals, particularly pups. In all, 27 sites were examined. Six new sea lion breeding colonies were documented, at Four Hummocks, Price, North Rocky, Dorothee, West Waldegrave and Nicolas Baudin Islands. All were found or confirmed by ground survey. Pup numbers were equivalent to 12% of the total number of pups estimated in surveys conducted from 1987 to 1992, but primarily in 1990. The sighting of brown pups on aerial surveys of Ward Island, Middle and Western Nuyts Reef supports earlier indications, based on dead pups, that they are breeding colonies. The timing of pupping seasons is not synchronous; estimates are presented for colonies between 1995 and early in 2004, with predictions to the end of 2005. The abundance estimates of sea lion pups highlight the importance of visiting a colony early in the pupping season to determine when pupping begins and ~5 months later when the maximum number of pups is expected. For the New Zealand fur seal, small numbers of pups were recorded at Dorothee, West Waldegrave and Nicolas Baudin Islands, and at Nuyts Reef. These and the previously unknown sea lion breeding colonies on the west coast of South Australia suggest that further colonies may remain to be documented. Because planning for aquaculture ventures is active in South Australia, it is important that the localities and status of sea lion and fur seal colonies be established unequivocally to ensure that the need for Prohibited Area status for islands with breeding colonies and for Marine Protected Areas around them is noted.


2006 ◽  
Vol 273 (1603) ◽  
pp. 2901-2907 ◽  
Author(s):  
Rebecca Lewis ◽  
Tamsin C O'Connell ◽  
Mirtha Lewis ◽  
Claudio Campagna ◽  
A. Rus Hoelzel

The evolution of resource specializations is poorly understood, especially in marine systems. The southern elephant seal ( Mirounga leonina ) is the largest of the phocid seals, sexually dimorphic, and thought to prey predominantly on fish and squid. We collected vibrissae from male and female southern elephant seals, and assessed stable C and N isotope ratios along the length of the vibrissae. Given that whiskers grow slowly, this sampling strategy reflects any variation in feeding behaviour over a period of time. We found that isotopic variation among females was relatively small, and that the apparent prey choice and trophic level of females was different from that for males. Further, males showed a very broad range of trophic/prey choice positions, grouped into several clusters, and this included isotopic values too low to match a broad range of potential fish and cephalopod prey tested. One of these clusters overlapped with data for South American sea lions ( Otaria flavescens ), which were measured for comparison. Both male southern elephant seals and southern sea lions forage over the continental shelf, providing the potential for competition. We discuss the possibility that individual southern elephant seals are pursuing specialist foraging strategies to avoid competition, both with one another, and with the South American sea lions that breed nearby.


Check List ◽  
2016 ◽  
Vol 12 (6) ◽  
pp. 2015 ◽  
Author(s):  
Luis Felipe S. P. Mayorga ◽  
Renata Hurtado ◽  
Ralph Eric Thijl Vanstreels ◽  
Renata Cristina Campos Bhering ◽  
João Luiz Rossi Junior

To improve the knowledge of the occurrence of pinnipeds along the coast of Espírito Santo state, Brazil, we compiled occurrence data of pinnipeds from the period from 1987 to 2010 based on the scientific literature, newspapers and novel observations. Twenty-two records were found, which correspond to three species: South American Fur Seal (Arctocephalus australis), Subantarctic Fur Seal (Arctocephalus tropicalis), and Southern Elephant Seal (Mirounga leonina). All records of pinnipeds are limited to the state’s southern coast (south of 20˚07ʹ S), which is consistent with the southern origin of these vagrant individuals. However, there may be bias due to the larger human population density in that region and the greater likelihood of observation. All records for which the date is known occurred during June to September, the austral winter. These records demonstrate that although the Espírito Santo coast is more than 2,000 km north from the nearest breeding colony of these species, it may still serve as wintering grounds for vagrant pinnipeds.


2002 ◽  
Vol 29 (2) ◽  
pp. 185 ◽  
Author(s):  
P. D. Shaughnessy ◽  
R. J. Kirkwood ◽  
R. M. Warneke

The abundance of Australian fur seal pups was determined at Lady Julia Percy Island in early January 2000 when the average age of pups was 5 weeks. A mark-recapture procedure with repeated recapture sessions was used to estimate abundance of pups in six accessible breeding areas. Pups (n = 1836) were marked by clipping guard hair on the head. Recaptures were conducted visually on 2-4 occasions, when a mean of 41% of sighted pups had been marked. Pup numbers were calculated using a modified Petersen estimate and combined by taking their arithmetic mean. The combined estimate in the accessible breeding areas was 4487 380 pups were counted at two inaccessible sites and 347 dead pups were recorded. Overall, the estimate of abundance for Lady Julia Percy Island was 5214 pups. This exceeds three previous estimates of doubtful veracity for pupping seasons in 1935-36, 1975-76 and 1986-87, and is the greatest number of pups recorded at any Australian fur seal colony. Summation of the most recent estimates of abundance of Australian fur seal pups in all colonies indicates pup production of 16 900 per annum in the 1990s. New Zealand fur seals were also breeding on the island (a mating and four new-born pups were recorded) and two adult male Australian sea lions were observed.


1999 ◽  
Vol 26 (3) ◽  
pp. 383 ◽  
Author(s):  
T. E. Dennis ◽  
P. D. Shaughnessy

In December 1996, a survey by helicopter of the Baxter Cliffs region of the Great Australian Bight in Western Australia did not locate any previously unreported colonies of the Australian sea lion or New Zealand fur seal. Although geologically contiguous with the Bunda Cliffs in South Australia (where sea lions have a scattered distribution), the Baxter Cliffs appeared generally more weathered and stable, with fewer collapsed sections of cliff forming platforms and providing habitat for seals. In total, 29 Australian sea lions were observed during the survey. Most were at a previously surveyed site approximately 2 km west of Twilight Cove. Ten other sites were recorded as potentially providing haul- out opportunity for sea lions; they were mainly caves and deep overhangs with access from the sea. No fur seals were seen. From this survey and from other records, we estimate the Australian sea lion population along the Baxter Cliffs in the Great Australian Bight region of Western Australia at less than 100 animals.


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