Related by context. Frequent words. (Click for all words.) 77 population 72 Populations 64 subpopulations 55 species 54 deer herds 54 breeding colonies 54 genetic variability 53 habitats 52 communities 52 subpopulation 51 birthrates 50 genetic diversity 50 avian species 49 amphibian populations 49 mortality 49 grassland birds 48 waterbirds 48 habitat fragmentation 48 communties 48 habitat 48 bee populations 48 insect populations 47 caribou herds 47 wolf populations 47 subgroups 47 predation 47 mammal species 46 Yellowstone ecosystem 46 genetically distinct 46 Population 46 subspecies 46 lineages 46 terrestrial ecosystems 46 nesting habitat 45 Sage grouse 45 vertebrate species 45 freshwater ecosystems 45 rookeries 45 ecosystems 45 breeding pairs 45 communites 45 temperate forests 45 regions 45 concentrations 45 pronghorns 44 demographically 44 herds 44 taxa 44 mammals 44 censuses 44 epidemics 44 socioeconomically 44 clades 44 colonies 44 nestlings 44 tiger mosquito 44 migratory 44 enrollments 44 forest ecosystems 44 ecologies 43 migratory species 43 amphibian species 43 ant species 43 migrations 43 overhunting 43 migratory patterns 43 fox squirrels 43 densities 43 bird species 43 mosquito populations 43 salmonids 43 aquatic habitats 43 Alaskan natives 43 interbreeding 43 threadfin shad 43 temperate regions 43 translocations 42 sagebrush habitat 42 Critically Endangered 42 native brook trout 42 black footed ferret 42 nesting pairs 42 mortalities 42 crocodilians 42 aquatic ecosystems 42 deer herd 42 primate species 42 brant 42 arthropod 42 polar bear populations 42 refuges 42 HIV prevalence 42 salmon fisheries 42 ungulates 42 apex predators 42 spotted owls 42 depopulating 42 temperate zones 42 grebe 42 migratory routes 42 mammalian species