Body growth in Hawaiian monk seals
نویسندگان
چکیده
Body length and axillary girth measurements of more than 600 free-ranging Hawaiian monk seals from 1 to 20 yr old were analyzed. Comparison of fitted von Bertalanffy growth models confirmed there is no evidence of sexual dimorphism in this species. Substantial differences in growth patterns were detected among seven subpopulations representing the species entire geographic range. The age at which seals would be expected to attain a reference length of 180 cm ranged from just over 3 yr up to almost 7 yr at the various sites. Subpopulations exhibiting slower growth have previously been found to also exhibit lower age-specific reproductive rates. Differences in growth of seals among sites likely indicate varying environmental conditions determining growth during the time periods represented in the sampled data.
منابع مشابه
Thermoregulatory Behavior of the Hawaiian Monk Seal (
The behavior of Hawaiian monk seals at French Frigate Shoals was studied in order to obtain information on their adaptation to a tropical climate. The seals were unable to remain on the dry beach platform during the day except during very high winds, extensive cloud cover, or rain. The seals characteristically moved down to wet sand on the beach slope during the day and returned to the beach pl...
متن کاملAn integrated approach for assessing translocation as an effective conservation tool for Hawaiian monk seals
For threatened and endangered species, translocations have been widely used to mitigate multiple sources of mortality that threaten population recovery. Although numerous Hawaiian monk seals Neomonachus schauinslandi have been translocated for a variety of purposes, few monk seal translocations have addressed the problem of prey limitation. To assess the efficacy of using translocations to miti...
متن کاملHAWAIIAN MONK SEAL (Monachus schauinslandi) STOCK DEFINITION AND GEOGRAPHIC RANGE Hawaiian monk seals are distributed predominantly in six Northwestern Hawaiian Islands (NWHI) subpopulations at French Frigate Shoals, Laysan and Lisianski Islands, Pearl and Hermes Reef, and Midway and Kure
STOCK DEFINITION AND GEOGRAPHIC RANGE Hawaiian monk seals are distributed predominantly in six Northwestern Hawaiian Islands (NWHI) subpopulations at French Frigate Shoals, Laysan and Lisianski Islands, Pearl and Hermes Reef, and Midway and Kure Atoll. Small numbers also occur at Necker, Nihoa, and the main Hawaiian Islands (MHI). Genetic variation among NWHI monk seals is extremely low and may...
متن کاملBiogeography and taxonomy of extinct and endangered monk seals illuminated by ancient DNA and skull morphology
Extinctions and declines of large marine vertebrates have major ecological impacts and are of critical concern in marine environments. The Caribbean monk seal, Monachus tropicalis, last definitively reported in 1952, was one of the few marine mammal species to become extinct in historical times. Despite its importance for understanding the evolutionary biogeography of southern phocids, the rela...
متن کاملIntegrating multiple technologies to understand the foraging behaviour of Hawaiian monk seals
The objective of this research was to investigate and describe the foraging behaviour of monk seals in the main Hawaiian Islands. Specifically, our goal was to identify a metric to classify foraging behaviour from telemetry instruments. We deployed accelerometers, seal-mounted cameras and GPS tags on six monk seals during 2012-2014 on the islands of Molokai, Kauai and Oahu. We used pitch, calcu...
متن کامل