Intraspecific specialization: foraging behaviors of the threespine stickleback, Gasterosteus aculeatus

The present longitudinal study examines a natural population of threespine sticklebacks, Gasterosteus aculeatus form Little Mud Lake in British Colombia, Canada to determine if individual fish within a given population exhibited a preference for finding prey on the bottom of the lake, prey floating in the water column of the lake, or prey in other microhabitats of the lake. Foraging behaviors were recorded to determine the presence of individual specialization within the focal sympatric population. Comparing the proportion of strikes on various microhabitats for multiple individuals shows that individual specialization is present within the focal population of sticklebacks. Data shows that some fish prefer the feed on benthic prey while others prefer to feed on prey found on the surface of the water. Diet preferences were also compared to morphology to determine if individual fish traits had a relationship to preferred foraging location. Length of the longest gill raker and protrusion length results showed a relationship to limnetic-like and benthic-like feeding behaviors.