UNIT 8 Wildlife Populations

Wildlife—all animals that live freely in the natural environment – Includes game & nongame species

Game species—animals that are legally hunted, trapped, or fished Characteristics of game species: – Body parts are used (meat, fur or hide) – Population numbers high enough to replace annual losses, including from hunting – Are challenging to hunters

U.S. Fish & Wildlife categories of game species – Big game (black bear, deer, elk, moose) – Small game (gray squirrel, rabbit) – Upland bird (ruffed grouse, pheasant, partridge) – Migratory bird (woodcock, common snipe) – Waterfowl (Canada goose, ducks, snow goose) Game Species Categories

Nongame species—cannot be hunted, trapped, or fished – Songbirds, birds of prey, loons – Endangered & threatened species

Minnesota has over 600 species of wildlife – 83 mammals (21 game species) – 22 amphibians – 29 reptiles – 319 birds (45 game species) – 147 fish (50 game species) MN Species of Wildlife

Mammals—endothermic (warm-blooded) vertebrates; also: – Produce milk to feed their young (mammary glands) – Have hair or fur – Are heterodonts—2 sets of specialized teeth Identifying characteristics of mammals: – Pelts, skulls & teeth, scat, tracks Mammals

Skulls can be used to identify species & diet Mammal Skulls

Skulls can be identified based on: – Size (length & width) of skull – Size of key parts: Brain case Cheek bone (zygomatic arch) Snout (rostrum) Eye sockets (orbits)

Dental formula—number of different types of teeth – Look at upper or lower jaw – Count number of teeth & types on one half of the jaw Dental formula: UPPER Incisors, Canines, Premolars, Molars LOWER Incisors, Canines, Premolars, Molars

Four types of teeth: – Incisors: in front; gnaw or cut – Canines: longest teeth; stab or tear – Premolars: 2 cusps (points); crush or shear – Molars: 3-5 cusps, in back; grind

Scat can be used to identify species & diet Mammal Scat

Scat can be identified based on: – Size, color, amount – Shape of scat: Spherical (herbivore) Cylinders (carnivore/omnivore)

Tracks identify movement pattern, group of mammal, & species Mammal Tracks

Walker/Trotter – 2 lines (zig-zag) of prints – Rear & front prints the same – Ex: dogs, cats, deer 4 Movement Patterns

Bounders – Usually 2 rear prints show – Rear prints land on front prints – Ex: weasels, mink, otter

Waddlers – 2 prints – Rear prints alongside, or in front of front prints – Ex: bear, beaver, raccoon

Hoppers – 4 prints – 2 rear prints in front of front prints – Ex: rabbits, squirrels

Fish—ectothermic (cold- blooded) vertebrates; also: – Have fins & gills – Have a swim bladder – Lateral line system senses surrounding objects Fish

Birds— endothermic vertebrates; also: – Have feathers – Capable of true flight – Lay hard-shelled, water-tight eggs Birds

Reptiles & amphibians—ectothermic vertebrates; also: – Amphibians have moist, thin skin – Reptiles have dry, scaly skin – Both lay eggs Amphibian eggs have no shell Reptile eggs have a leathery shell Blanding’s Turtle video clip Reptiles & Amphibians

Population—a group of the same species that live together in the same place – Many populations can live in the same habitat Measuring Wildlife Populations

General survey—record everything you see & hear – Used to determine what species (& how many) are present – Survey compares one year’s numbers to previous year’s numbers – Ex: track survey, call survey

Sampling survey—count part of the population, then estimate total population – Plot-based (Quadrant) method—count all individuals in an area Used for non- moving species (plants)

Quadrant method formula: Population = (# indiv. in a quadrant) x (total area) Ex: aerial surveys, pellet counts

– Mark-recapture method—capture & mark indiv. in a sample, release, & recapture another sample to estimate total population Mark-recapture formula: Population = (# marked) x (total # caught) (# recaptured in 2 nd sample) Ex: bird banding, radio collaring