1. Allie Schmalz

2. Process where adult animal return to birthplace to reproduce Marine animals Ex. Sea turtles and salmon

4. Sea Turtles Separate feeding grounds and nesting sites Females lay eggs on beach (50-200 eggs) Two months incubation time Salmon life history video

5. Social Facilitation Olfactory cues Geomagnetic Imprinting Not mutually exclusive hypotheses

6. Young females follow experienced breeders Not natal beaches but sites where they’ve had success Meylan experiment disproved this hypothesis in green turtles (1990)

7. Olfaction = smell Odorants trigger olfactory system Water enters nasal openings, specialized epithlial cells come in contact with odorant Signal sent to oflactory bulb which processes it Odorant memory during parr smolt transformation alevin > fry > parr > smolt > post-smolt > salmon > kelt Specific odorants may help navigation to specific locations Not long distance

8. Earth magnetic field Distinct poles Magnetic field line intersect Earth’s surface at different angles = inclination angle Magnetic “fingerprint” Super sensitivity to magnetic field Imprint on birthplace

9. Meylan 1990 Distinct genotypes show no gene flow between sites

10. Nevitt 1994 Fish exposed to PEA were more likely to choose arm B when PEA is present

11. Lohmann 2008 When exposed to magnetic fields turtles swam in the direction of their home site

12. Social facilitation (mostly disproved) Olfactory cues Geomagnetic imprinting May be a combination of these Geomagnetic imprinting- long distance navigation Olfactory cues- more short range navigation

13. Small sample sizes Permission to tag animals Not animals in their natural habitats, possible effects on behavior Ex. Salmon study

14. More satellite tracking Global warming effects on natal homing Pole reversal Effects of habitat destruction

16. Do you think the benefits of natal homing outweigh the costs? How do you think natal homing evolved? Why don’t all species use this method? Are there any characteristics of the species that use this method successfully? If females put all this energy into reproduction (specifically turtles) then why is there little to no parental care? Natal Homing dude!