lakes, ponds, potholes, hot springs, sinkholes, and seasonal melt water or spring fed ponds are all viable brook stickleback territories. Though the species can thrive in these habitats, primary spawning, breeding, and rearing grounds are located in shallow (< 1.5m) near shore environments with high vegetation cover and low velocity water. The species has a wide elevation range with specimens identified from sea level to ~ 2,400m. Diet The brook stickleback is an omnivore, with primary feeding tendencies toward aquatic insect larvae, adult terrestrial insects, crustaceans, fish eggs and larvae, snails, oligochaetes, nematodes, rotifers, and mites. However, brook stickleback feed on vascular plant material, as well as algae. Newly hatched stickleback larvae and planktonic crustaceans from both streams and ponds. Juveniles eat small organisms due to mouth size restrictions, and adults eat both large and small organisms. Predators Certain large invertebrates, birds, mammals, and fish all prey on the brook stickleback. With its small size, this species of stickleback has evolved piercing spines and protective plates to hinder predators. With this protection, as well as advanced anti-predator behavior, the brook stickleback is only a minor prey item. In a lab study, adult water bugs (Lethocerus americanus) and dragonfly nymphs (Aeschna spp.) both successfully preyed on the stickleback, but only in a night setting. Fish have been observed to be the most successful predator of the brook stickleback. Examples of these fish predators include yellow perch (Perca flavescens), rock bass (Ambloplites rupestris), creek chub (Semotilus atromaculatus), burbot (Lota lota), central mudminnow (Umbra limi), smallmouth bass (Micropterus dolomieu), largemouth bass (Micropterus salmoides), northern pike (Esox lucius), brook trout (Salvelinus fontinalis), rainbow trout (Oncorhynchus mykiss) and round goby (Neogobius melanostomus). Brook stickleback eggs can be cannibalized, as well as consumed by rainbow trout (Oncorhynchus mykiss). Competition among the ninespine stickleback exists. However, ninespine stickleback habitat exists in the pelagic zone, while the brook stickleback occupies the littoral zone. In the presence of fathead minnows (Pimephales promelas), the brook stickleback has a more diverse diet since the fathead is a more generalist feeder. Life history For this particular species, spawning occurs in mid-summer. Brook sticklebacks migrate annually up affluent streams and creeks of rivers and lakes during the spring to spawn in weedy areas. Spawning occurs as males secure a protected territory and construct a nest. These nests are constructed using algae, roots, and aquatic vegetation. There is one entrance with no exit. When