210 likes | 361 Views
Resource Selection and Scale. Habitat (resource) Selection Levels of Selection Multiple Scale Studies Methodological Issues. Behavioral Mechanisms of Resource (Habitat) Selection. The Problem:
E N D
Resource Selection and Scale • Habitat (resource) Selection • Levels of Selection • Multiple Scale Studies • Methodological Issues
Behavioral Mechanisms of Resource (Habitat) Selection • The Problem: • We look at distributions of animals among habitats and try to infer what habitats are most important to our species of interest • This allows us to compare use of habitat to availability of habitat (which is often defined as selection, but does not allow us to say ANYTHING about preference of habitat
Problem Results Because Distributional Pattern Choice • Predators may promote habitat specificity without selection by the prey • pepper moths • Sessile organisms may have distribution affected by dispersal agents • plankton, barnacles---wave action • Competitive exclusion may force animals to settle in suboptimal habitat
The Solution? • Detailed behavioral study • Understand the mechanism that produces distributional pattern • If all else is equal is a certain habitat selected over another? • Usually takes lab and field approach
Habitat Selection by Tits (Partridge 1978) Wild Birds Hand- reared • Wild and hand-reared birds show preferences when given equal access to oak and pine in lab • Coal tits prefer pine • Blue tits prefer oak • Genetic component to selection indicated by hand-reared birds Percentage of Time
Choices Made by Tits Are Adaptive • Coal tits better at foraging skills needed in pines • Blue tits better at foraging skills needed in oak Skills Appropriate for: Pine Oak Detecting Cammo Prey Ability to Tear and Hack
As With Tits, Most Studies Indicate Choices are Innate, but Modified by Experience • Red-legged and Cascade Frog Tadpoles (Wiens 1972) • RL--live in naturally striped backgrounds (sticks, cattails, etc) • C--live in square backgrounds (gravel) • Preference for squares by cascade reduced by raising on stripes--visa versa for red-legged Squares C Selection C RL RL Stripes Raised on square background Raised on striped background
Features Important in Habitat Selection(Verner 1975, Hilden 1965, Klopfer and Hailman 1965) • Food • Nest Sites • Song Posts, Hunting Perches, Shelter • Terrain • Vegetation • Previous Experience • Other Animals • Social stimulation • Colonial Animals--young often settle in established colonies (Herring Gulls, Drost 1958)
How Are Multiple Cues Integrated? • Summation (Hilden 1965) • each cue is added or subtracted to form a total score for a habitat • if score exceeds some threshold, animal settles • Niche Gestalt (James 1971) • habitat is responded to as a whole • Hierarchical Selection (Wiens and Rotenberry 1981) • large scale vs. fine scale selection
Natural Ordering of Selection Process (Johnson 1980) • First order • Selection of the physical or geographical range of a a species • Second order • Placement of the home range of an individual or social group within the species’ range • Third order • Use of various habitat components within the home range • Fourth order • Selection of resources from within areas within the home range (food selection at a foraging site, for example)
Scale Matters Need to understand differences in each animal’s grain and extent
Scale and Our Perception of Availability • Your insights and conclusions about resource selection are dependent upon your definition of resource availability • Availability in one sense defines the level in the ordered selection hierarchy • You define available as habitat within the home range or within the western US, etc. • But the point is—the investigator defines availability
New Sensors are Available to Better Define Availability • Animal-borne Video and Environmental Data Collection Systems • Sound, vibration • Pressure, depth • Acceleration • Travel speed rhythm, activity • Imagery • Blood flow / pressure, heart rate • Body orientation • Light • Temperature (internal, external) • Body fluid chemistry • Biopotentials Cooke et al. 2004 TREE Moll et al. 2007 TREE
Integrating Location and Behavior New Goal is to: Integrate multiple sensors to better understand the behavioral context of a location Rutz et al. 2007 Science
But Still We Define Available • My suggestion is to focus on use rather than use:availability. • GPS transmitters are constantly improving our view of what is used.
Habitat relationships of wildlife include multiple hierarchical levels and spatial scales • Capercaillie (Black Grouse) • Forest stand • Moderate canopy cover • Large stands • Home range • Old forest • Contiguous forest • Management is needed at landscape scale • European political structure does not allow • Hunters manage at stand scale for habitat structure(Storch 1997)
“Emergent” effect of habitat loss more than just reduction in area or reduction in connectivity • American Martin (Bissonette et al. 1997) • Substand • Mature forest with CWD, local variation • Stand • Old contiguous forest, except in Maine where even young forests and clearings are used because prey is abundant • Home range • Uniformly prefer mature forest • No selection in uniform old forest environments • Landscape • Consistent selection for areas with ~75% forest Effect of fragmentation was not evident until landscape scale was used, happens over smaller spatial extent outside of Maine where loss of forest results in patches of unsuitable habitat interspersed with suitable habitat
Managing for Goshawks at Multiple Scales(Finn et al. 2002, 2003) • Biologically-relevant scales need to be investigated • Managers must provide different resources at some scales • Strategies to statistically sort among the myriad of inter-related variables • Only include variables of biological and management relevancy • Weed out redundant variables • Conduct single scale analysis and later combine best predictors at each scale to determine important scales
Methodological Issues • How to sample across multiple scales (Brennen et al. 2002) • Too much data • Overpowering? • What is experimental unit? • Landscape, not the pixel • Spatial Autocorrelation
Discussion • In small breakout groups consider the Nielsen et al. reading. • Are they studying selection? Preference? • Do they define available? • What study design (according to Thomas and Taylor) is being used? • Is selection hierarchical and scale dependent? • How does selection vary within a season and why? • How are hypotheses (models) developed, evaluated, ranked? • How could a manager implement their research findings to better design forest harvest?
References • Wiens, JA, Van Horne, B., and BR Noon. 2002. Integrating landscape structure and scale into natural resource management. Pp. 23-67. In J. Liu and WW Taylor, eds. Integrating landscape ecology into natural resource management. Cambridge University Press. Cambridge, UK • Brennen, JM, Bender, DJ, Contreras, TA, and L Fahrig. 2002. Focal patch landscape studies for wildlife management: optimizing sampling effort across scales. Pp. 68-91. In J. Liu and WW Taylor, eds. Integrating landscape ecology into natural resource management. Cambridge University Press. Cambridge, UK • Finn, SP, JM Marzluff, and DE Varland. 2002. Effects of landscape and local habitat attributes on northern goshawk site occupancy in western Washington. Forest Science 48:427-436. • Finn, SP, DE Varland, and JM Marzluff. 2003. • Cody, ML. (ed.). 1985. Habitat selection in birds. Academic Press, San Diego, CA. • Fretwell, SD and Lucas, HL, Jr. 1969. On territorial behavior and other factors influencing habitat distribution in birds. Acta Biotheoret. 19:16-36. • Hilden, O. 1965. Habitat selection in birds. Annales Zoologici Fennici 2:53-75. • James, FC. 1971. Ordinations of habitat relationships among breeding birds. Wilson Bull. 83:215-236. • Klomp, H. 1954. De terreinkeus van de Kievit, Vanellus vanellus (L.). Ardea 42:1-139. • Klopfer, PH and JP Hailman. 1965. Habitat selection in birds. Advances in the Study of Behavior 1:279-303. • Klopfer, PH and JU Ganzhorn. 1985. Habitat selection: behavioral aspects. Pp. 435-453. In. M.L. Cody, ed. Habitat selection in birds. Academic Press, San Diego, CA. • Partridge, L. 1978. Habitat selection. Pp. 351-376. In. J.R. Krebs and N. B. Davies, eds. Behavioural Ecology, an evolutionary approach. Sinauer. Sunderland, MA. • Verner, J. 1975. Avian behavior and habitat management. Pp. 39-54. in Procedings of the Symposium on Management of Forest and Range Habitats for Nongame Birds, Tuscon, AZ. May 6-9 1975. • Wiens, JA. 1972. Anuran habitat selection: early experience and substrate selection in Rana cascadae tadpoles. Animal Behaviour 20:218-220. • Wiens, JA. 1985. Habitat selection in variable environments: shrub-steppe birds. Pp. 227-251 In. M.L. Cody, ed. Habitat selection in birds. Academic Press, San Diego, CA. • Wiens, JA. and JT. Rotenberry. 1981. Habitat associations and community structure of birds in shrubsteppe environments. Ecological Monographs 51:21-41. • Storch, I. 1997. The importance of scale in habitat conservation for an endangered species: the Capercaillie in central Europe. Pp. 310-330. In. JA Bissonette, ed. Wildlife and landscape ecology. Springer. New York. • Bissonette, JA, DG Harrison, DC Hargis, and TG Chapin. 1997. The influence of spatial scale and scale-sensitive properties in habitat selection by American marten. Pp. 368-385. In. JA Bissonette, ed. Wildlife and landscape ecology. Springer. New York. • Krausman, PR. 1997. The influence of landscape scale on the management of desert bighorn sheep. Pp. 349-367.. In. JA Bissonette, ed. Wildlife and landscape ecology. Springer. New York. • Matthysen E. and D. Currie. 1996. habitat fragmentation reduces disperser success in juvenile nuthatches. Sitta europaea: evidence from patterns of territory establishment. Ecography 19:72-76. • Johnson, D. H. 1980. The comparison of usage and availability measurements for evaluating resource preference. Ecology 61:65-71. • Rutz, C. et al. 2007. Video cameras on wild birds. Science 318:765. • Moll, R. J. et al. 2007. A new “view” of ecology and conservation through animal-borne video systems. Trends in Ecology and Evolution 22:660-668. • Cook, S. J. et al. 2004. Biotelemetry: a mechanistic approach to ecology. Trends in Ecology and Evolution 19:334-343.