Pacific Angelshark: Squatina californica

Family: Squatinidae

Common name(s)

Pacific Angelshark, Californian Angel Shark.

Identification

A large angelshark species with short, un-fringed, spatulate barbells. Anterior nasal flaps weakly fringed. Elongated spiracles wider than eye width. Distance from eye to spiracle about 1.5x eye width. Concave forehead between eyes. Rows of thorns prominent in juveniles; small or absent in adults.
Dorsal coloration light tan to reddish brown with numerous very small dark spots and some eye-sized dark spots. Two larger dark spots form ocelli (fake eye spots) on each pectoral fin. Dorsal margin white. Ventrum pale.

Size

Maximum size 175cm. Size at birth 25-26cm.

Habitat

Sub-tropical and temperate sandy substrates, often close to monumentation such as rocky reefs or kelp forests where food is abundant. Inshore to edge of continental shelf. From 2-200m. More commonly 3-100m.

Distribution

Eastern Pacific. From southeast Alaska to Baja California. Records from the Pacific coast of South America likely refer to the South Pacific Angel Shark (Squatina armata).

Conservation Status

NEAR THREATENED

Historically, the Pacific Angel Shark was discarded at sea or used as bait, but in the 1970s a commercial fishery in California began targeting this species. A rapid increase in Pacific Angel Shark landings between 1983-1986 occurred in California (Richards 1987), leading to concern that stocks could be overexploited. Even though a minimum size was proposed for the gillnet fishery targeting both California Halibut (Paralichthys californicus) and Pacific Angel Shark, this measure proved not to be effective at reversing the declining population levels along the Santa Barbara/Ventura coast and Channel Islands areas, California (Richards 1987, Cailliet et al. 1993). Additionally, it was observed that declines in landings were occurring prior to the implementation of these management strategies indicating the over-exploitation of the species within the region (Leet et al. 2001).
In Mexico this species is caught in fisheries targeting elasmobranchs. Fishing effort in Mexico is challenging to quantify, as some fishers hold licenses but are inactive, while others may share a single license among multiple vessels (Sosa-Nishizaki, pers. comm. 2016). This species is now absent from regions in Baja California Sur where it was historically found in catches (Laguna San Ignacio and Bahia Magdalena), and there is also evidence for depensation in this region (Ramirez-Amaro et al. 2013).

Citation

Cailliet, G.M., Chabot, C.L., Nehmens, M.C. & Carlisle, A.B. 2020. Squatina californica (amended version of 2016 assessment). The IUCN Red List of Threatened Species 2020: e.T39328A177163701. https://dx.doi.org/10.2305/IUCN.UK.2020-3.RLTS.T39328A177163701.en. Downloaded on 23 January 2021.

Reproduction

Like other squatinids, the Pacific angelshark is an aplacental viviparous species. 1-11 pups per litter. Gestation approximately 10 months. Pups are born between March and June.

Diet

Feeds on small fishes including queenfish, blacksmiths, gobies and juvenile sea bass. Also consumes sea cucumbers.
The Pacific angelshark is an ambush predator that lays on the substrate partially covered by sand. When a fish swims within range, the angelshark explodes upwards from its concealment, mouth agape and clamps down on its prey.

Behavior

The Pacific angelshark remains motionless (waiting for prey to swim near its mouth) for long periods each day. Returns to the same resting/hunting spot each day. Presumably relocates if prey becomes scarce.

Reaction to divers

Easy to approach. Remains motionless, relying on camouflage. Will bolt if molested.

Diving logistics

The Pacific angelshark is quite common at various sandy areas adjacent to reefs or kelp forests in Southern California. At the West end of Santa Cruz Island they are very abundant. They are fairly abundant throughout the Northern Channel Islands. The deep sand around Ship Rock at Catalina is a good spot. And in the South Bay you can find them at Malaga Cove.
North of Santa Barbara, they can be encountered on shore dives at Tajeguas Beach.

The best way to search for angel sharks is to swim along the edge of the reef, about 2m above the sand, in rocky or kelpy areas where the sharks have sand they can hide under and access to a good supply of fishes.
Although the shark will likely be buried under a fine covering of sand, their outline is often somewhat visible. Even if the outline of the angelshark is obscured, they always keep their eyes and spiracles exposed. After a few encounters, you should be able to pick out the signs of a shark’s presence more easily.
Once you have located a shark, with slow, non-aggressive movements, it is usually possible to settle down next to it and gently fan away most of the sand to get a better look. This does not distress the animal or significantly waste its energy because one or two pectoral fin flaps will completely cover it again. Be careful not to wave your hand too close to its mouth to avoid a demonstration of its incredibly fast bite reflex!