Tracking Marine Animal Movements and Stable Isotopes in Ecology Flashcards
What is the simplest method to track animal movements?
Physical tagging (e.g., rings on birds, paint on snails, or tags on fish) and recapture at different locations.
What is telemetry?
A technique using electronic devices to record animal movements, environmental data, or communicate with satellites and acoustic receivers.
What are the advantages of modern telemetry techniques?
Allows tracking fine-scale movements of individual animals.
Provides detailed environmental data (e.g., temperature, pressure, acceleration).
Enables global tracking through satellite and acoustic arrays.
What do data storage tags record, and what are their limitations?
Record attributes like time, temperature, pressure, light, and acceleration.
Do not directly record location; infer location from light, tidal pressure, and time. Require the animal to be recaptured to retrieve data.
How do acoustic tags work?
Relay identification and data to acoustic receiver arrays.
Small, passive, and inexpensive but require costly receiver networks.
What is the Global Tracking Network?
A collaborative effort to establish ocean-scale acoustic receiver arrays and share data on tagged animals.
What are pop-off satellite tags, and how do they work?
Archive data (e.g., light, pressure, movement vectors) and transmit via satellite.
Connect to GPS for location only when at the surface. Larger than other tags, limiting use to larger species.
What advantage do satellite tags provide?
Shift focus from population-scale movements to detailed individual movement data.
What are natural tracers, and how are they used?
Substances naturally incorporated into tissues, such as isotopes, pollutants, or parasites.
Link the composition of these substances to the geographic or environmental origin.
Give examples of natural tracers.
Stable isotopes (e.g., carbon, oxygen, nitrogen).
Trace elements.
Parasites specific to certain regions.
What did tagging studies reveal about Atlantic bluefin tuna movements?
Extensive mixing occurs between Gulf of Mexico and Mediterranean spawning populations, especially Mediterranean fish moving to U.S. waters.
How do stable isotopes in otoliths help infer tuna origins?
Gulf of Mexico and Mediterranean waters differ in temperature, reflected in distinct oxygen isotope compositions in otoliths.
This helps determine the proportion of tuna from each spawning population in fisheries.
How can stable isotopes in baleen infer whale movements?
Baleen growth records isotopic compositions of the whale’s environment over time.
Isotope models link baleen composition to geographic locations. Behavioral models simulate whale movements to match baleen isotope data.
What was learned about ‘Hope’ the blue whale?
Her baleen recorded movements over the last 7 years of her life, showing seasonal migrations between feeding grounds.
What are stable isotopes, and why are they important in ecology?
Atoms with the same number of protons but different numbers of neutrons.
Provide insights into diets, movement, migration, and physiology.
