نتایج جستجو برای: شیربتarabibarbus grypus
تعداد نتایج: 362 فیلتر نتایج به سال:
Although the grey seal Halichoerus grypus is one of the most familiar and intensively studied of all pinniped species, its global population structure remains to be elucidated. Little is also known about how the species as a whole may have historically responded to climate-driven changes in habitat availability and anthropogenic exploitation. We therefore analysed samples from over 1500 individ...
Understanding the links between foraging behaviour and habitat use of key species is essential to addressing fundamental questions about trophic interactions and ecosystem functioning. Eight female grey seals (Halichoerus grypus) were equipped with time-depth recorders linked to Fastloc GPS tags following the annual moult in southwest Ireland. Individual dives were coupled with environmental co...
Many animal species segregate by sex. Such segregation may be social in nature, or ecological, or both. Grey seals (Halichoerus grypus), like many large mammals, are sexually size dimorphic. In size dimorphic species, allometric differences in morphology, metabolic rate and reproductive costs are likely. Such differences may require the sexes to use different foraging strategies or different ha...
An ecological risk assessment (ERA) was conducted for Shadegan Wetland in Iran. The objective of this study was to assess the risk to phytoplankton, zooplankton, invertebrate, insect larvae, and fish affected by pesticide in Shadegan Wetland. Five pesticides (DDT, Aldrine, Dieldrin, Ametryn and Lindane) were assessed to evaluate the impact to aquatic community in the Shadegan Wetland. The risk ...
A survey on myxosporean parasites of freshwater fishes from Mesopotamian part of Iran (south western part of the country, Khuzestan Province) was carried out. Some 280 individuals belonging to 14 different species were examined the prevalence of myxosporean parasites, morphology of the spores, plasmodial development, the infective site, and characteristics of the cyst location using the histolo...
بهعنوان یک اکوسیستم گسترده، تالابها مهیاکننده خدمات اکولوژیکی ارزشمندی هستند. آلودگیهای زیستمحیطی خصوصاً روانابهای ناشی از آفتکشها بایستی در امر حفاظت از سلامت تالاب موردتوجه قرار گیرند. هدف از ارائه این مقاله، ارائه روش واقعگرایانه جهت ارزیابی ریسک اکولوژیکی آفتکشها در تالاب شادگان میباشد. روش واقعگرایانه یا کسر ریسک (RQ)، بهوسیله تعیین غلظت آب و ارزش کل سمیت (TRV) برای 5 آفتکش د...
this study was conducted to determine taxonomic and zoogeographic features of fishes from the kor and helleh river basins in southwestern iran. the specimens were collected from 2004 to 2007. twenty four species belonging to 20 genera, 9 families, and 6 orders from the kor river basin and 21 species belonging to 19 genera, 8 families, and 6 orders from helleh basin were identified. ichthyofauna...
In-Air Evoked Potential Audiometry of Grey Seals (Halichoerus grypus) from the North and Baltic Seas
In-air anthropogenic sound has the potential to affect grey seal (Halichoerus grypus) behaviour and interfere with acoustic communication. In this study, a new method was used to deliver acoustic signals to grey seals as part of an in-air hearing assessment. Using in-ear headphones with adapted ear inserts allowed for the measurement of auditory brainstem responses (ABR) on sedated grey seals e...
Maternal behaviour is a crucial component of reproduction in all mammals; however the quality of care that mothers give to infants can vary greatly. It is vital to document variation in maternal behaviour caused by the physiological processes controlling its expression. This underlying physiology should be conserved throughout reproductive events and should be replicated across all individuals ...
A retrospective survey was performed on the presenting conditions of 205 live grey seal pups (Halichoerus grypus) admitted to the Cornish Seal Sanctuary in Gweek, United Kingdom between May 2005 and March 2011. The purpose of the survey was to examine the prevalence of various presenting signs at the sanctuary. The presenting signs were classified into nine non-mutually exclusive categories: oc...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید