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Macrocystis and  Nereocystis luetkeana

Like huge fingers that disappear into the depths of the sea, the Giant Kelp Forests found in the waters off north America, are the rainforests of the sea.

Kelp leaves called fronds can grow up to 50 centimetres a day. Kelp forms dense canopies up to 35 metres above the seabed. Most of us eat kelp regularly, by consuming icecream or jelly. Products made from kelp are used to thicken these foods, and other products like toothpaste.

Held upright by gas-filled bladders at the base of leaflike blades, kelp fronds grow straight up to the surface, where they spread across the top of the water to form a dense canopy...

Sebastes spp.

Rockfish are a diverse and important group of marine fishes, with over 70 different types to be found along the Northeast Pacific coast and over 100 worldwide. They come in a rainbow of colours, as evidenced by their names: Black Rockfish, Canary Rockfish, Yellowtail Rockfish, and so on.

They are members of the scorpion fish family, (Scorpaenidae), so it should be no great surprise that the spines on the fins are sometimes venomous, and skin punctures can be very painful. The different species enjoy a number of habitats. Some live in the rocky reefs, some linger within the canopy of the kelp forests, and some inhabit the deep seafloor. They are prevalent in every underwater habitat from the sub-tidal down across the continental shelf and beyond 8,000 feet deep...

Hexagrammos decagrammus

The kelp greenling (Hexagrammos decagrammus) grows to a length of 60 cm. The mouth is small, terminal and directed upwards. The upper jaw reaches the anterior point below the eye orbit. The snout is blunt with thickened lips and the moderate teeth are in rows on the sides of the jaws and in patches at the tip. The head is conical and compressed. It has one notched dorsal fin, a rounded caudal (tail) fin and an anal fin with one dorsal spine. There is an erectable cirrus (slender tentacle) above and behind each eye and a small pair of cirri in between the eyes and dorsal fin.

Males are brown to olive with blue or copper; blue spots on the head and anterior portion of body. Each blue spot has a round ring of reddish spots...

Ophiodon elongatus

The body of the lingcod is elongate, tapering and only slightly compressed. The head is elongate and conical, the mouth is large with numerous large teeth. Lingcod are generally dark brown with lots of spots and blotches on the upper part of the body, but come in a variety of colours ranging from blue green to red brown.

They occur between Point San Carlos, Baja California, and Kodiak Island, Alaska. They are not abundant south of Point Conception except in a few localities. They live at or near the bottom, generally in close association with rocky areas and kelp beds, especially where there is a strong tidal movement...

Lutjanidae

The snappers are a large and diverse group of robustbodied, carnivorous fishes. Most species possess relatively large mouths with stout canine teeth and bodies covered with relatively large, coarse scales. They are frequently brightly coloured. They are demersal (spending most time swimming close to the sea bed) in some cases down to 450m and are found in the tropical and sub topical waters of the Atlantic, Indian and Pacific Oceans.

There are over one hundred individual species globally, but within the Pacific Coast Sub-tropical eco region there are only a limited number of species that you are likely to see at diving depth, and these will tend to be in the warmer waters of the region.

Haliotis sorenseni

The white abalone is the only mollusk currently listed under the Endangered Species Act by the National Marine Fisheries Service (NMFS). NMFS designated the white abalone as a candidate for listing in 1997 for the California region south to Baja California, Mexico. A short-lived commercial fishery began in the early 1970s, peaked middecade and collapsed in the 1980s. Only occasional landings occurred after that time. It was also sought after by recreational divers, but actual landings are unknown. Recent studies suggest that this species has likely suffered reproductive failure resulting from severe over-harvest. The fishery was closed in 1996.

The white abalone dwells in deep waters – 25 to over 65 metres (80 to 200ft) from Point Conception (southern Californ...

The Palinurus genus (frequently transcribed as Panulirus) is represented by numerous species in all of the world’s tropical and sub-tropical seas as well as more temperate waters. It is a predatory, nocturnal animal with a vividly decorated coat. They are often numerous locally; they linger in crevices (with their long antennae sticking out) during the day and hunt small benthic organisms at night, but they also feed on organic detritus whenever they happen across it.

Lobsters have recently suffered a dramatic demographic decline; intensive fishing has annihilated entire populations, especially where tourism abounds. Please record all sightings of lobsters, identifying individual species where possible...

Serranidae

When people talk about coral reefs, fishermen tend to shrug their shoulders and complain about snagged lines and torn nets. But when you talk about groupers, they suddenly sit up and pay attention. Groupers are among the economically most important fishes of the coral reef, because of their popularity as food. Yet without the coral reef there would probably be no groupers. For this reason, groupers are an extremely important indicator species and your record of their existence or non-existence during your dive tells us a lot.

The goliath grouper (Epinephelus itajara), sometimes called the jewfish is classified as critically endangered on the IUCN Red List. Found in shallow, inshore waters to depths of 45m, this indicator prefers areas of rock, coral, and mud bottoms...

Identifying sharks in the wild is a great challenge! While scientists can spend weeks examining every detail of a species, divers may encounter a shark for only a few seconds or minutes. Many species look alike and one individual may not be identical to the next. There are, however, relatively few species in any one specific dive site and with some preparation and a little practice it is possible for all of us to recognise the more common and distinctive species. The key to successful shark identification underwater is a process of elimination, based on a mental checklist of the main features to look for in every animal encountered. One feature alone is rarely enough for a positive identification, so gather as much information as you can before drawing firm conclusions.

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Asteroidea, but not A. vulgaris or A. forbsii

Sea stars (group name Stelleroidea) are sometimes called starfish, though lacking both vertebrae and fins, they are not real fish. There are two sub-types of sea stars: Asteroideas are the true sea stars and sun stars, whereas Ophiuroideas are brittle stars and basket stars.

Ophiuroid means ‘snake-like’, referring to the form and motion of the arms. The arms of brittle stars are easily broken off, but will regenerate in a few days to weeks. Sea stars can also regenerate arms that are broken off, but for most species, the central region of the body must remain intact Class Asteroidea, the true sea stars, contains about 1700 living species of these echinoderms...