Ornithology Final

Flocks

a group of birds

Colonies

a large group of birds, often the same species, that nest or roost together in one place for protection, breeding, and foraging benefits

Pair-based/Group territoriality

Many birds defend exclusive territories for breeding, feeding, or nesting. Territories may be defended by a mated pair or by cooperative groups.

Hierarchical Relationships

Some bird species establish dominance hierarchies that determine access to food, mates, or nesting sites.

Extended Families

Extended family systems involve cooperative breeding, where offspring from previous years help parents raise new young. This system is common in stable environments where territories are limited.

Social Monogamy

Birds that just have one mate

Social Polygyny

One male mates with multiple females.

Social Polyandry

One female mates with multiple males.

Social Promiscuity

When monogamous species engage in mating outside of their bonded pairs

Cooperative breeding

When non-parental relatives help raise offspring that are not their own

intrasexual competition

Members of the same sex compete with each other for sexual access to members of the other sex

Intersexual Competition

Females choose between male mates.

Differential parental investment

For most, eggs are more expensive than sperm, so males contribute less than females. One sex may also contribute more to parental care, making ornaments more costly for them

Bateman's principle

The sex that invests the most in offspring will become a limiting resource over which the other sex competes

Fisher's hypothesis

Refers to positive feedback between trait and preference. Genes for traits and preferences will become associated

Good genes Hypothesis

the hypothesis that an individual chooses a mate that possesses a superior genotype

Direct Benefit Hypothesis

The trait being selected by females provides a direct benefit to the fitness of the male. Trait is directly beneficial to male fitness.

Anthropogenic Causes of Bird Mortality

Cats, Window collisions, Pesticides/agriculture, Wind turbines, Climate change, Habitat loss

Lacey Act

A U.S. act that prohibits interstate shipping of all illegally harvested plants and animals.

Pittman-Robertson Act

-Imposed a sales tax on guns to fund wildlife restoration, research and public education

Endangered Species Act

(1973) identifies threatened and endangered species in the U.S., and puts their protection ahead of economic considerations

Habitat Conservation Plan

A plan that attempts to protect one or more species across large areas of land through trade-offs or cooperative agreements

Natural Community Conservation Plan

California-based, ecosystem-level conservation program designed to protect entire natural communities while allowing compatible economic development.