نتایج جستجو برای: endangered fish

تعداد نتایج: 117273  

2013
Jon C. Bedick Brett C. Ratcliffe Leon G. Higley JON C. BEDICK BRETT C. RATCLIFFE LEON G. HIGLEY

The endangered American burying beetle, Nicrophorus americanus Olivier, presently occurs in small and widely scattered areas on the periphery of its former range. As part of the recovery plan for this insect implemented by the U.S. Fish and Wildlife Service (USFWS), we conducted surveys in Nebraska to ascertain its presence. Additionally, we examined various trapping methods and procedures in t...

Journal: :ecopersia 2015
maryam nasrollah pourmoghadam soheil eagdari bagher mojazi amiri hadi poorbagher nima nemati mobin

the pollution of aquatic ecosystems may affect natural reproduction of fish populations by decreasing the fertilization efficiency. among the various sources of pollution, heavy metals are important group, being found in both freshwater and marine environment. the present study investigated changes of sperm characteristics of caspimyzon wagneri when exposed to manganese (mn). spermatozoids were...

2000
Julie P. Hawkins Callum M. Roberts Victoria Clark

Coral reefs are the most diverse ecosystem in the sea. Throughout the world they are being overfished, polluted and destroyed, placing biodiversity at risk. To date, much of the concern over biodiversity loss has centred on local losses and the possibility of global extinction has largely been discounted. However, recent research has shown that 24% of reef fish species have restricted ranges (<...

2009
JEFFREY M. DAMBACHER KIM K. JONES DAVID P. LARSEN

—In response to a petition to list Great Basin redband trout (subspecies of rainbow trout Oncorhynchus mykiss) as threatened or endangered, the U.S. Fish and Wildlife Service conducted a status review in 1998. To support that review, we conducted a survey of the abundances of redband trout in each of six subbasins of the Great Basin that included the states of Oregon, California, and Nevada. We...

2013
ANDREW B. STEIN VIRGINIA HAYSSEN

Panthera pardus (leopard; Linnaeus, 1758) is the smallest of the 4 large felids in the genus Panthera. A solitary and adaptable species, P. pardus is the widest ranging of all wild felids, inhabiting rain forests, mountains, semiarid environments, and suburban areas throughout sub-Saharan Africa, the Middle East, and South Asia to the Russian Far East. Despite this distribution, P. pardus is li...

2015
James E. Deacon Paul B. Schumann Edward L. Stuenkel

—Critical thermal maxima (CTM) and thermal preferenda of the common fishes of the Virgin River were examined. Differences in final temperature preferenda and CTM for species with low thermal lability (speckled dace, spinedace, roundtail chub) correspond well with differences in their distribution and abundance in the river. These species shifted their acute thermal preferences relatively little...

Journal: :Biology letters 2007
Russell B Wynn Simon A Josey Adrian P Martin David G Johns Pierre Yésou

Global climate change is driving rapid distribution shifts in marine ecosystems; these are well established for lower trophic levels, but are harder to quantify for migratory top predators. By analysing a 25-year sightings-based dataset, we found evidence for rapid northwards range expansion of the critically endangered Balearic shearwater Puffinus mauretanicus in northeast Atlantic waters. A 0...

Journal: :The Journal of heredity 2006
Kimberly C Pause Robert K Bonde Peter M McGuire Robert T Zori Brian A Gray

Published cytogenetic data for extant cetacean species remain incomplete. In a review of the literature, we found karyotypic information for 6 of the 13 tentatively recognized species of the suborder Mysticeti (baleen whales). Among those yet to be described is the critically endangered North Atlantic right whale (Eubalaena glacialis). Herein, we describe and propose a first-generation G-banded...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید