Herpetology Notes PDF

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Summary

All notes were taken throughout the semester for each lecture.
Dr. Hecnar...

Description

Animals move n space to acquire resources (ie food, shelter, mates) Herps move less than other vertebrates – Sample patches as move Return to specific sites – orientation Spatial structure of landscape and population (Barriers to movement conservation issue) Methods  Mark/recapture: Toe clips, tags, paint, tattoo, brand, PIT, patterns, radio tracking  Continuous monitering best: Max. n. fixes  Map movements over time Types of movement  Station keeping: Foraging, commuting, territorial defense  Ranging behaviour: -Dispersal (one way) –Migration (two way) Home Range and Territory: all the areas routinely visited or travelled  Size: Amount of resources required to survive  Differs – few to thousands m2 Salamanders < Frogs < Lizards < Snakes < Turtles Size related to distribution of resources, renewal rates, body size, and natural history  Herbivores: Smaller ranges, move less  Predators: Larger, or shift activity (eg gila and bearded lizards : 20-70 ha)  Insectivores: Rapid renewal of food, sit & wait, but other forage widely (skinks, teiids)  Turtles: Sea turtles - 1000s km2 Freshwater - 2 ha Some species having shifting activity centres, few appear nomadic Territory: That part of home range that is defended Well studied, esp. lizards Evolves when resources moderately abundant & energy gain > cost of defense Common in insectivores “sit and wait” lizards, geckos Mating of physical resources usually more important than food  Mating system: males range larger and overlaps females (Floaters occur)  Site defense: Smaller area protected (eg. plethodonts: log) (eg. Anurnas: breeding site defense) Migration  Leave home range to another distant area (Often annual: breeding, hibernacula)  Habitat loss Amphibian breeding migrations  Synchronized spring breeding site (Temp important, rain trigger, usually nocturnal) Not long distance  Most frogs:...