Species-of-the-Day Wood Duck (Aix sponsa)

Brink of Extinction By early 1900’s, culminative effects of: 1) wetland drainage (ag. expansion) 2) deforestation 3) overhunting

Habitat Wooded swamps & river bottomlands Natural tree cavities for nesting (cypress, sycamore, silver maple, black ash) Home range changes with flooding events

Food * In water <18”, feed on: - seeds of trees (e.g., acorns) - also field grains * Young = aquatic insects

Reproduction Pairing in late Oct into spring (Mar-July nest) Clutch size = 6-10 eggs Behavior -Dump nests (up to 30+ eggs in 1 nest) = “egg dumping” behavior = intraspecific brood parasitism -may decrease hatch rates to 10%

Factors Determining Patterns of Habitat Use Competition Predation

Concept of Habitat Selection Wildlife perceiving correct configuration of habitat needed for survival – differences based on age/experience/chance? – hierarchy to decision process Niche concept (time/place/functional role) & habitat selection For example, in open habitats, bats use low- frequency / long-distance calls (ultrasound) while foraging Whereas, bats in closed canopy settings = constant/high frequency = detect wing beats

Hutchison’s n-dimensional hypervolume

Concept of Habitat Selection Hutchison = n-dimensional hypervolume as explanation of the niche Fundamental vs. Realized Niche Species 1 Species 2

Testing the Hutchinsonian Niche Concept of Habitat Selection James – work with birds in Arkansas…quantified habitat relationships How do birds select habitat? niche gestalt : each species has characteristic perceptual world…responds to that world as organized whole … search image concept How do we (as wildlife biologists) “see” through the eyes of wildlife species?

Wildlife Habitat Ecology & Mgt Habitat from an evolutionary perspective Species distribution relative to habitat dist’n Climatic events Pleistocene Epoch & dist’n of modern species

habitat interspersion – Leopold’s Law of Interspersion

Habitat Fragmentation 1) gap formation 2) decrease patch size 3) increase isolation 4) increase edge 5) conversion of matrix

Concepts Habitat = species-specific resources available (relative quality) Habitat Use = manner in which species use resources Habitat Selection = hierarchical decision process (innate & learned) of what habitats to use Habitat Preference = based on selection of habitat, which are used more than others (preferred vs. avoided)

Concepts Habitat Availability = accessibility of resources Habitat Quality = positive relation with fitness (not just density) Critical Habitat = resources essential to the species….ESA designation….How is it determined?

Scale Dependence of Habitat Selection 1 st Order 2 nd Order 3 rd Order 4 th Order Macrohabitat vs. Microhabitat 1 st order – innate? 2 nd order –decisions 3 rd &4 th order –decisions

Need for Multiscale Analysis e.g., Australian leadbeater’s possum landscape vs. local scales

Constraints (significance) Level of Focus (level of interest) Components (explanation) Hierarchy Theory

Constraints Why do long-tailed weasels select forest patches and fencerows in fragmented landscapes? Components Population Community Individual

Guild Concept guild = group of species that exploit the same class of resources in similar way community guild = no taxonomic restrictions; guild members chosen based on investigator-defined resources assemblage guild = guild members based on taxonomic relations

Models of Habitat Relationships Model (assess) habitat for wildlife species, e.g., USFWS Habitat Suitability Index (HSI) models -include top 3 environmental variables related to a species’ presence, distribution, & abundance HSI = (V 1 x V 2 x V 3 ) 1/3 = 0 to 1

Yellow Warbler HSI for different forest conditions

HSI models useful for representing possible major habitat factors true value as hypotheses Do not provide information on: -population size or trend -behavioral responses single-species approach

Species-of-the-Day Kirtland’s warbler (Dendroica kirtlandii)

Habitat NE Michigan jack pine forests -Nesting habitat = 2-6 m (~5-20 ft) tall young jack pines (<15 yrs) = very dense stands -Large forest stands = 100+ ha (200+ A)

2001 = 1,085 singing males = highest count since 1951

Food Insectivores & herbivores

Reproduction ~May, late May = 5 eggs i.p. = days Behavior -Migrate to Bahamas -Return to MI early to mid May (males 1 st ) -Influence of brown- headed cowbirds (nest parasitism)

ecotones, coverts, edges The “Edge Effect”

Core Areas – Interior Habitat “Not all habitat patches are the same” habitat-interior species Area-sensitive species

Countering Edge Effects & Habitat Fragmentation Increase edge complexity

Countering Edge Effects & Habitat Fragmentation Develop connective corridors Increase edge complexity

Linking Core Areas & Refuges

Multiple-Use Module (MUM) Network Refuges (nodes) connected by corridors

Roads: Formation of Barriers in Landscapes

Species-of-the-Day grizzly bear (Ursus arctos)

Habitat Mississippi R to Pacific (plains, forests, mountains, wetlands, beaches)… Today, (US, lower 48) Montana Wyoming Idaho Washington

1985 – Interagency Grizzly Bear Committee

Food Omnivores – up to 90% plant matter * Seasonality

Reproduction ~mid May to early July litter size = up to 2 *delayed implantation Behavior Hibernation (Oct-May)