Because of a lapse in government funding, the information on this
website may not be up to date, transactions submitted via the
website may not be processed, and the agency may not be able to
respond to inquiries until appropriations are enacted. The NIH
Clinical Center (the research hospital of NIH) is open. For more
details about its operating status, please visit
cc.nih.gov. Updates
regarding government operating status and resumption of normal
operations can be found at
opm.gov.
Periodic movements of animals in response to seasonal changes or reproductive instinct. Hormonal changes are the trigger in at least some animals. Most migrations are made for reasons of climatic change, feeding, or breeding.
Periodic movements of animals in response to seasonal changes or reproductive instinct. Hormonal changes are the trigger in at least some animals. Most migrations are made for reasons of climatic change, feeding, or breeding.