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Inshore Waters (inshore + water)
Selected AbstractsPopulation biology of the red gurnard (Aspitrigla cuculus L.; Triglidae) in the inshore waters of Eastern Anglesey and Northwest WalesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 4 2010A. L. Marriott Summary ICES has identified red gurnard Aspitrigla cuculus (L.) as a potential commercial species and recommended that monitoring programmes should be conducted to derive information on biological parameters for stock assessment purposes. In this paper, data on the population biology of red gurnard in the coastal waters of Northwest Wales and Eastern Anglesey are presented. Total length (TL) of fish sampled ranged from 15.4 to 35.0 cm (males) and 10.5 to 43.1 cm (females), with the majority of females between 20 and 30 cm TL (70.0%) and males between 20 and 30 cm TL (71.0%). TL/weight (W) relations were similar between immature and mature individuals for both sexes and between both sexes (all maturity stages combined), producing a combined data equation W = 0.005 TL3.19. Age of fish ranged from 1 to 7 years and 1 to 6 years, respectively, for females and males, with the majority of females age 3 (37%) and the majority of males age 2 (49%). The age structures of female and male red gurnards were significantly different, with the older age classes consisting predominantly of female fish. Both males and females exhibited similar asymptotic growth patterns; the combined von Bertalanffy growth function was . Instantaneous rates of total mortality were calculated as 1.13 year,1 for males and 0.98 year,1 for females. The size (L50) and age at first maturity (A50) were estimated to be 26.3 cm TL and 3.6 years for males, 28.1 cm TL and 3.5 years for females and 25.6 cm TL and 3.7 years for both sexes combined. [source] ABUNDANCE OF BOTTLENOSE DOLPHINS IN THE BAYS, SOUNDS, AND ESTUARIES OF NORTH CAROLINAMARINE MAMMAL SCIENCE, Issue 1 2003Andrew J. Read We conducted a mark-recapture survey of bottlenose dolphins Tursiops truncatus in the bays, sounds, and estuaries of North Carolina during July 2000, using photographic identification techniques. During this survey we took 7,682 photographs of dolphins and, of these, 3,457 images were of sufficient quality for analysis. We identified 306 dolphins from distinctive nicks and notches on their dorsal fins. Eighry-six dolphins were photographed on more than one occasion during the course of the survey; one dolphin was photographed on four separate days. We then applied the results of our photographic analyses to several mark-recapture models and examined potential violations of the assumptions of these models, including an unexpected correlation between photo quality and mark distinctiveness. Our analysis suggests that our results are robusr to possible violations of these assumptions. The resulting estimates were then scaled to account for the proportion (0.46) of unmarked dolphins in the population. Our best estimate of the number of dolphins present in the inshore waters of North Carolina during July 2000 is 1,033 with a 95% Confidence Interval of 860,1,266 (CV = 0.099). Most dolphins were found in the northern part of the study area, which includes the second largest estuarine system in the United States. [source] Isolation and characterization of eight microsatellite loci from Picnic seabream (Acanthopagrus berda)MOLECULAR ECOLOGY RESOURCES, Issue 4 2006C. T. JEAN Abstract Acanthopagrus berda (Sparidae) is abundant in estuaries and inshore waters of the tropical Indo-Pacific oceans. Because of the drastic decrease in the species' wild populations, there is an urgent need to understand its population structure. Eight microsatellite loci were isolated from A. berda. An analysis of 50 individuals from Tapeng Lagoon, southwestern Taiwan demonstrated a low degree of diversity. The allelic numbers ranged from nine to 20. The observed heterozygosity (HO) ranged from 0.28 to 0.64 (mean, 0.45). We also investigated the prospective value of the microsatellite primers to examine whether they were applicable to related taxa. [source] Animal behaviour and marine protected areas: incorporating behavioural data into the selection of marine protected areas for an endangered killer whale populationANIMAL CONSERVATION, Issue 2 2010E. Ashe Abstract Like many endangered wildlife populations, the viability and conservation status of ,southern resident' killer whales Orcinus orca in the north-east Pacific may be affected by prey limitation and repeated disturbance by human activities. Marine protected areas (MPAs) present an attractive option to mitigate impacts of anthropogenic activities, but they run the risk of tokenism if placed arbitrarily. Notwithstanding recreational and industrial marine traffic, the number of commercial vessels in the local whalewatching fleet is approaching the number of killer whales to be watched. Resident killer whales have been shown to be more vulnerable to vessel disturbance while feeding than during resting, travelling or socializing activities, therefore protected-areas management strategies that target feeding ,hotspots' should confer greater conservation benefit than those that protect habitat generically. Classification trees and spatially explicit generalized additive models were used to model killer whale habitat use and whale behaviour in inshore waters of Washington State (USA) and British Columbia (BC, Canada). Here we propose a candidate MPA that is small (i.e. a few square miles), but seemingly important. Killer whales were predicted to be 2.7 times as likely to be engaged in feeding activity in this site than they were in adjacent waters. A recurring challenge for cetacean MPAs is the need to identify areas that are large enough to be biologically meaningful while being small enough to allow effective management of human activities within those boundaries. Our approach prioritizes habitat that animals use primarily for the activity in which they are most responsive to anthropogenic disturbance. [source] Occurrence of killer whales in Scottish inshore waters: temporal and spatial patterns relative to the distribution of declining harbour seal populationsAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 6 2009Harriet E. Bolt Abstract 1.Sightings of killer whales around Shetland were recorded between 1991 and 2006 and for the whole of Scotland for 2007. The data were used to investigate temporal patterns in killer whale occurrence around Shetland and spatial patterns in occurrence around Scotland. 2.There was a strong seasonal peak in sightings around Shetland during June,July, coinciding with the harbour seal pupping season. 3.There was no clear trend in annual sightings around Shetland between 1991 and 2006. 4.Killer whales were sighted most frequently around Shetland and the Pentland Firth as well as around Mull and the Treshnish Isles. 5.These findings are discussed in terms of potential impacts upon local declining harbour seal populations and future research requirements. Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||