Beach & ravens
 
 

Seashore and Ocean

Information below taken from:
Seashore LIfe at Torrey Pines State Natural Reserve
Photo by Eva Armi
by Carol and Peter Lucic

 

Climate

View of Torrey Pines State BeachTorrey Pines State Natural Reserve is located in an area which lies closer to the equator than to the north pole. Because of this, our waters are almost semi-tropical and possess many marine organisms with close relatives from farther south. Our coastal climate is characterized as Mediterranean - that is, with mild winters and temperate summers, which encourages the occurrence of marine flora and fauna that are transitional between true tropical and true temperate.

 

California Current

The general circulation of ocean water in the northern hemisphere of the Pacific is clockwise around the entire ocean basin. Therefore, the overall current off the coast of California and Torrey Pines State Natural Reserve is from north to south and is known as the California Current. This current brings water from the higher latitudes--off Alaska, the Aleutian Islands, and Siberia. This makes for cool water along our coast, especially at depth, and therefore some cool water types of plants and animals are able to live here despite our relatively warm climate.

 

Upwelling

Because of several factors, surface water off Southern California (including Torrey Pines) often does not move parallel to shore but slightly away from it and ends up going out to sea. Because there is no water on the land to move in and replace this water, colder water comes up from below to take its place near the shore. This process is called "upwelling" and causes the near shore water to be much cooler than would otherwise be the case.

Upwelling can cause local coastal fog. When a mass of warm dry air, known as a Santa Ana, moves from the land to the sea, it comes to rest several miles out from the coast. The lower part of this air becomes cooled and moistened by the ocean water and forms what is called a stable marine layer. In time the airflow reverses and moves this layer back toward land. As it approaches the shore, it encounters the colder upwelled water which further cools this air to the point at which fog is formed. The advancing fog bank envelops the coast and delivers large quantities of life-giving water to the shoreline flora. It is thought that the Torrey pines would not have survived our Mediterranean climate without such fogs.

 

Tides

For tidal information click here: Scripps site

 

If your feet were anchored to the beach and the tide came in and covered your head, could you hold your breath until the tide went out again? The reverse of this is what many intertidal animals must do twice each day, as they are able to "breathe" only when covered by seawater. Some marine animals such as fish last but a short time out of the water and others, such as the periwinkle, can survive out of water for as long as two months. Most of these "long breath holders" have discovered a way of trapping small quantities of water within their shells to help them survive in the reverse way that a SCUBA diver carries air in tanks to breathe underwater.

The intertidal area may be subdivided into four zones: · Splash Zone: e.g. the top of Flat Rock and several feet higher · High Intertidal: top to side of Flat Rock · Medium Intertidal: side to below bottom of Flat Rock · Low intertidal: below bottom of Flat Rock

Examples of benchmark plants and animals and their zones are given below.

When the tide is out, the animals left high and dry are, for the most part, under varying degrees of stress. First, they are starved for oxygen; second, they are exposed to terrestrial predators (such as humans); and third, many cannot eat. They seek shelter in crevices, under rocks, beneath the sand, or in their shells and wait until the tide covers them and lets them become active again.

Seashore Plants and Animals in Rocky Areas

Splash Zone: Mostly rock is visible with a few animals visible here.

The Rock Louse, a gray-green bug-like animal, lives here and cannot tolerate being submerged. A small dirty-gray snail, the Periwinkle, is diagnostic of this zone and is plentiful on top of Flat Rock. Also present is the tiny Small Acorn Barnacle and various Limpets, These latter have gray-green to brown shells that look like flattened cones stuck to the rock.

High Intertidal Zone: Slightly more rock is covered with living things.

The Periwinkles, Acorn Barnacles, and Limpets continue and, a little lower the Black Turban Snail and the Owl Limpet are found. This limpet is like the others except that it is bigger and smoother and is often found in its own depression on the rock. Shore Crabs may be seen crawling about investigating the sessile (attached) inhabitants. Hermit Crabs may also be seen. Chitons, stationary slug-like animals with segmented shells, are conspicuous. Rockweed as well as Red and Pink Encrusting Algae. starts to be evident.

Middle Intertidal Zone: At least half the rock is occupied by attached life.

At the high end of this zone are mussel beds, and the lower limit is marked by green surf grass. The most conspicuous assemblages of this zone are the aggregates of California Mussel and necked Goose Barnacles. Also seen at Flat Rock are honeycomb-like Sand Castle Worms, which build their houses out of cemented sand grains.

Below the mussel beds are many more organisms. The Aggregate Sea Anemone is present where the mussel bed is not well developed. This anemone may occur in colonies of thousands of individuals and is covered by shell fragments and other detritus. These anemones are squishy and wet when out of the water but open into a concise and beautiful flower-like patch when submerged. A close relative is the Giant Green Anemone which lives usually as a solitary individual Anemone and is larger than the Aggregate Anemone.

Also found in this zone are two medium large barnacles. One is the Pink Barnacle with pink stripes on the shell and the other is the Thatched Barnacle, which is more conical, has a smaller opening, and tends toward a more solitary habit.

The snails of this zone are the Purple Olive, which often leaves its tracks in the sandy-bottomed tidepools, the Gem Murex, found on rocks, and the California Cone. Coffee Bean Shells also occur here, as well as Volcano Limpets. Occasionally a large, dark purple sea slug, the Sea Hare, may be seen here.

Common tidepool fish in this zone and below are the Wooly Sculpin and the Opaleye.

Plants in this zone are the pink encrusting California lithothamnium, which lines the bottoms of many tidepools, the Circular Pink Alga, which forms small circular pink patches, and several forms of what are known as Coralline Red Algae with their small and jointed branches. The brown seaweeds of this zone are the long Feather Boa Kelp and the stiff Sea Palm.

Low Intertidal Zone: Almost all rock is covered with plant life.

You know you're in this zone because of the predominant seaweed known as Green Surf Grass, which flourishes from this level to as deep as twenty feet subtidally. This is not an alga but is actually a flowering plant which has become adapted to a marine habitat. It forms large, emerald-green masses on rocky bottoms and is commonly confused with Eel Grass by the layman. True Eel Grass lives intertidally in bays and estuaries where there is little or no wave shock and occurs as deep as 100 feet subtidally on muddy substrates.

Many of the same animals which live in the middle intertidal zone also live in the low intertidal. In addition, many subtidal animals may be found in this zone. Examples are the Spiny Lobster, young Moray Eels, brick red to purple Kelp Crab, and a rare sea star (more commonly known as Starfish).

 

Seashore Plants and Animals of Sand beaches

Two sand fleas are found on our beach: one is the light colored Large Beach Hopper and the other is the grayish or brownish Small Beach Hopper. The former resides deep in the sand during the day, and the latter hides in clumps of rotting seaweed.

Clams present in the sand are the small Bean Clam, sometimes seen by the hundreds, and the much larger Pismo Clam, which is usually buried. Fragments of other clams which may be found are the Broad Eared Scallop, Common Littleneck, Macoma, and the rock boring Piddock.

Crabs which may be present are the Common Sand Crab and, at very low tides, the much larger Spiny Sand Crab.

Empty tests (shells) of the Sand Dollar are often washed up on the beach, although the living animals are found only some distance from the shore, where the bottom is deep enough to protect them from wave action.

Also hidden beneath the sand is the red Beach Bloodworm. These creatures may be detected by the many small holes they leave on the surface of the sand.

Pieces of Giant Kelp are often washed up on the beach with their "leaves" and small attached bladders. Also washed up may be the remains of Elk Kelp, which has a long, whiplike stipe (stalk) terminating in a large, bulbous bladder with attached "horns."

Many other plants and animals live along the shores of Torrey Pines State Natural Reserve. In order to learn more about them, the interested person would do well to start with the following recommended references:

Hedgepeth, Joel and Hinton, Sam. Common Seashore Life of Southern California, Naturegraph. 1961.

Hinton, Sam. Seashore Life of Southern California. U. C. Press. 1987.

Hubbs, Carl and Whitaker,.Thomas, Editors. Torrey Pines State Reserve. Torrey Pines Association, 1972.

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Information below taken from Vertebrates of Torrey Pines Reserve
by D. Hunsaker

Marine Mammals: Whales, Dolphins, Seals, and Sealions

There are several species of marine mammals which can be observed in the coastal area and out to sea. Triangular fins above the surface do not always mean a shark, so keep a close eye for groups of porpoises and whales which have distinctive dorsal fins. Since the porpoises and whales are air-breathing mammals, they periodically come to the surface to inhale and exhale. In the process, a portion of the back, including the blow hole and dorsal fin are exposed above the surface of the water, and this approach to the surface, and rolling dive in which the back is exposed, is indicative of porpoises. They usually travel in small groups, which also serves to distinguish them from sharks. The porpoises and whales which occur off the coast include the Pacific Bottlenose Porpoise (Tursiops gillii), the Dall Porpoise (Phocoenoides dalli), the Pacific White-sided Porpoise (Lagerhynchus obliquidens), the Pacific Dolphin (Delphinus bairdii), the Pilot Whale (Globicephala scammonii), the Fork-striped Porpoise (Stenella caeruleoalba) and the Killer Whale (Orcinus orca). Two sperm whales can be occasionally observed, the Pygmy Sperm Whale (Kogia breviceps) and the Sperm Whale (Physeter catodon). The Arch-beaked Whale (Mesplodon carlhubbsi) and the Goose-beaked Whale (Ziphius cavirostris) have also been reported off the coast. The most popularly known whale is the Gray Whale (Eschrichtius gibbosus), which migrates to the lagoons of Baja California for breeding and birth. The migration begins in late fall when the whales traveling singly or in small groups can be seen off the coast adjacent to the Reserve, traveling at slow speeds. When they arrive at the large shallow lagoons of Baja California the females give birth to their young, nurse them, and rest in anticipation of the return to the north. Breeding takes place before the migration back to the Alaskan waters begins. January finds the whales moving back north again accompanied by the small babies which swim with the mothers.

The other marine mammals which can be expected to occur in the waters of the Reserve are the Seals and Sealions; the Harbor Seal (Phoca vitulina) and the California Sealion (Zalophus californianus). The Harbor Seal reaches a length of about 6 feet and weighs less than 300 pounds. It can be identified by the grayish-yellow blotches which form a mottled pattern over a darker ground color. There are no external ears. The hind flippers always are extended directly out from the body, they cannot be brought forward, as they can in sealions.

The California Sealion is considerably larger than the Harbor Seal, with the males reaching a maximum of 8 feet and weighing close to 1000 pounds with the female growing to 6 feet and 300 pounds. Sealions can use their hind flippers in locomotion so they are often seen sunning themselves on rocks several feet above sea level, and the Harbor Seals are usually much closer to the sea. The sealions breed on the Channel Islands from May until August and the Harbor Seal mates in September. Pups are born about a year later.

 

Flat Rock

by Docent Judy Schulman

Located just south of the foot of the Beach Trail is a freestanding Delmar Formation structure called Flat Rock.  It has also been referred to as Indian Bath Tub Rock. At its top, there is an approximately 5’ by 6’ foot hole that at one time went down about 4’ There are several stories as to how the “excavation” came to be. These include that it was actually an Indian bathtub, a hollow to provide fish for the missionaries, a human sacrificial altar, and a place a hermit used for preserving his daily catch of fish.

The truth is that it is the remains of a turn of the century coal mine. While visiting his cousin, a Del Mar deputy sheriff in the 1890s (some sources say 1870s, others 1880s), Welshman, William Bloodworth discovered, at low tide, a coal vein some distance off shore. Another version of the story says that he discovered pieces of the black fuel on the beach while on a Sunday picnic. In either case, he used Flat Rock to employ a common mining method used in Wales. He planned to sink a shaft at shoreline and then go beneath the ocean to tunnel out horizontally about 100’ to the coal deposit. He was able to get to about 15‘ down before waves and high tide made it impossible

to go any further. Despite building a trough, the shaft kept getting filled with water, rock, and sand. He was never able to tunnel out into the ocean.

Bloodworth’s scheme wasn’t all that far-fetched. There are several references about coal in this area. Charles Christopher Parry was sent here in 1850 as part of the U.S. –Mexican Boundary Survey to look for coal deposits on the ocean bluffs. Accounts say that low-grade coal deposits were found near the coastal area near Torrey Pines. Some sources report that ranchers were said to collect chunks of coal that washed on shore and used these as fuel.

There are three versions as to how Flat Rock became separated. In version one, it is a sea stack which is the result of continual erosion from wind and water. In version two, workers from the old Del Mar Hotel separated it from the mainland in order to build a roadway. Hotel carriages would take guests on picnic drives beside the water to the present site of Scripps Beach. In version three, a stage company proposed operating a stage line between Del Mar and La Jolla. In any case, it was possible to use the road only during extremely low tides.

Excerpted from September 2009 Torreyana

For more information on:

    Flat Rock stories, see Hank Nicol’s book Notes from the Naturalist.

    Geology of Torrey Pines area, see Don Grine’s section here on this website.

 

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Aerial photos of Torrey Pines State Beach
 

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