Appearance
This fish reaches up to 38 cm in length. It is brownish to olive to iridescent purple dorsally, becoming lighter on the sides and yellowish/golden on the belly. Below the eye is a whitish patch and black crescent. A young individual may have a dark saddle-mark. "P. notatus" has wide pectoral fins and a narrow but rounded tail fin.Status
"P. notatus" is not a threatened species. It is widespread and apparently not in decline.Behavior
Except when breeding, the typical habitats for this marine fish are sandy and muddy bottoms from shallow water just below the tide to depths of 366 m.Its diet includes crustaceans and fish. It is nocturnal, feeding at night and resting during the day, when it buries itself in the sand.
Habitat
Except when breeding, the typical habitats for this marine fish are sandy and muddy bottoms from shallow water just below the tide to depths of 366 m.Its diet includes crustaceans and fish. It is nocturnal, feeding at night and resting during the day, when it buries itself in the sand.
Reproduction
This fish is oviparous, and the male is dimorphic, designated as Type I and Type II. The Type I male claims a nest site, which is generally under a rock in the intertidal zone. Once the female spawns, she leaves the eggs in the care of the male and departs. One female can lay up to 400 eggs, and the number of eggs varies directly with body size. The male may mate with a few females and end up with over 1000 eggs in his nest. The eggs and larvae adhere to the wall of the nest. The male tends them by fanning them, keeping the nest clean, and hydrating them if they begin to desiccate at low tide. He protects the larvae post-hatching until they reach their juvenile stage and leave the nest, about 45 days after fertilization. Very occasionally, an egg will yield twin larvae.Type II male is much smaller in size than the Type I. There are significantly fewer Type II males than Type I males within reproductively active populations of males, with a Type I to Type II ratio around 9:1. In contrast to Type I males, Type II males do not defend nests or guard eggs, but rather sneak in to the nest sites of Type I males and fertilize the eggs there. Type II males at times display behavior of fanning their own sperm into a nest containing a gravid female. The ratio of gonad weight to body weight of Type II males is on average nine times greater than that of Type I males. Type II males can be mistaken as gravid females as their abdomen distend due to enlarged testes.
The conditions of the intertidal breeding habitat change regularly with the tide. A male that tends to his nest can become stranded as the tide recedes, even becoming beached completely out of the water. The fish tolerates this well. It can breathe air....hieroglyph snipped... Physiologically, it is well adapted to hypoxia, as well as hypercapnia. Even its sperm are quite functional in low-oxygen conditions.
Predators
This fish is an important prey for the bald eagle in some coastal areas, being the most common food provided to eaglets by their parents in one study on Vancouver Island. This is a concern, however, because this fish has been found to contain relatively high levels of contaminants, such as dioxin. It is also prey for the northwestern crow, the glaucous-winged gull, and the great blue heron. It is eaten by seals and sea lions."P. notatus" is host to the parasitic copepods "Lepeophtheirus remiopsis" and "Hamaticolax prolixus".
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