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Fauna of Point Reyes
Tule Elk
Emerging from the swirling fog, the herd of tule elk makes a primeval tableau as they slowly forage along the cliffs at the northern end of Point Reyes National Seashore. The elk are impressive animals with magnificent antlers and heavy winter coats. The sight must have been commonplace to the Coast Miwok people who lived on the Point Reyes peninsula before it was colonized by European settlers.
Reports from Sir Francis Drake mention thousands of very large deer wandering inland from the coast. The combination of hunting and the loss of the native vegetation to agriculture and livestock led to the gradual extinction of tule elk at Point Reyes in the late 1850’s.
Adult tule elk were reintroduced to Tomales Point in 1978. The original group of 13 elk (2 males and 11 females) has now grown to seven herds totalling more than 500 elk. There is an ongoing program to reduce their population growth through contraception of the cows.
Late summer is rutting season. The males grow huge antlers, four feet wide and up to five feet high. A set of antlers can weigh up to 40 pounds. Sometimes two young males will spar, antlers interlocked, for the right to take over a harem. Usually only the male leader will impregnate the females, though occasionally a young aggressive buck will take his chances. The calves are born in the spring. They nurse for four or five months, but start nibbling on grass when less than one month old. Cows, which can calve annually, give birth to one calf at a time. Elk are renowned as one of the most polygamous mammals in the world, with one male having a large harem.
Park policy is to extend the range of the elk in the park. Twenty-seven elk have been transferred to the Limantour Wilderness Area. The Mount Vision fire cleared excessive brush, making it suitable habitat for these magnificent animals.
Mountain Lion
...Felis concolor azteca
The first recorded photograph of a mountain lion in Marin County was taken by an automated camera set up after the Mount Vision fire. Over a period of three days, 12 pictures of a mountain lion at night were taken 1/2 mile north of the Bear Valley Trail. Images of the same mountain lion were also recorded near Point Reyes Hill. The camera takes a picture when a beam of light is interrupted. The lion here was photographed at 5:39 pm on August 30, 1998 in the wilderness area. The camera was set up by Scott Berendt, a biologist technician who works with research biologist Gary Fellers from the Biological Resources Division of the US Geological Survey.
Several people, including myself, have heard the eery sound of the mountain lion on the Inverness Ridge. Unlike the roar of an African lion, the mountain lion sounds more like the scream of a woman. There have been no attacks on people in this park.
About half of California is prime mountain lion country. This simple fact is a surprise to many. These large, powerful predators have always lived here, preying on deer and other wildlife, and playing an important role in the ecosystem. The status of the mountain lion in California evolved from ‘bountied predator’ between 1907 and 1963, meaning monetary incentives were offered for every mountain lion killed, to ‘special protected mammal’ in 1990. The change in legal status reflects growing public appreciation and concern for mountain lions.
Like any wildlife, mountain lions can be dangerous. With a better understanding of mountain lions and their habitat, we can coexist with these magnificent animals
ANATOMY: Strong jaws and teeth adapted to seize and kill. Can drag prey up to its own size to secluded spots to eat later. Though most cats’ eyes contract to a slit, the mountain lion’s eyes remain round. Their legs are strong, which allows them the speed to kill quickly.
SENSES: Excellent binocular vision for judging distance to its prey.
LOCOMOTION: Lions have tremendous leaping power, because the hind legs are longer than the forelegs. They can leap 18 feet in one jump. The tail is used for balance. They walk on their toes, rather than their soles and are silent runners because of retractable claws. They stalk prey.
ACTIVITY PERIOD: Nocturnal; normally hunting at night, but may be forced to hunt during the day if prey is scarce.
SOCIAL UNIT: Solitary except for breeding and when the female is raising cubs.
REPRODUCTION: Females breed at three years of age. There is no definite breeding season; thee to four cubs are born after 90-96 days. Cubs are weaned at three months.
Physical appearance: The mountain lion is tawny-colored with black-tipped ears and tail. Although smaller than the jaguar, it is one of North America’s largest cats. Adult males may be more than eight feet long, from nose to end of tail, and generally weigh between 130 and 150 pounds. Adult females can be seven feet long and weigh between 65 and 90 pounds. Mountain lion kittens, or cubs, are covered with blackish-brown spots and have dark rings around their tails. The markings fade as they mature.
Mountain lions are very powerful carnivores and normally prey upon deer, elk, and large animals. However, they can survive preying on small animals as well. They usually hunt alone, at night. They prefer to ambush their prey, often from behind. They usually kill with a powerful bite below the base of the skull, breaking the neck. They often cover the carcass with dirt or leaves and may come back to feed on it over the course of a few days. Their generally secretive and solitary nature is what makes it possible for humans to live in mountain lion country without ever seeing a mountain lion.
An adult male's home range often spans more than 100 square miles. Females generally use smaller areas — about twenty to sixty square miles.
In California, mountain lion populations have grown. In 1920, a rough estimate put their number at 600. Since then, more accurate estimates, based on field studies, revealed a population of more than 2,000 mountain lions in the 1970's. Today's estimate ranges between 4,000 and 6,000.
A mountain lion's natural life span is probably about 12 years in the wild and up to 25 years in captivity. Natural enemies include other large predators such as bears, lions and, at one time in California, wolves. They also fall victim to accidents, disease, road hazards and people. Generally, mountain lions are calm, quiet and elusive. They are most commonly found in areas with plentiful prey and adequate cover. Such conditions exist in West Marin. Consequently, the number of mountain lion–human interactions has increased. Even so, the potential for being killed or injured by a mountain lion is quite low compared to many other natural hazards. There is a far greater risk, for example, of being struck by lightning than of being attacked by a mountain lion.
WHAT SHOULD YOU DO IF YOU ENCOUNTER A MOUNTAIN LION?
There's been very little research on how to avoid mountain lion attacks. But mountain lion attacks that have occurred are being analyzed in the hope that some crucial questions can be answered: Did the victim do something to inadvertently provoke an attack? What should a person who is approached by a mountain lion do — or not do? The following suggestions are based on studies of mountain lion behavior and analysis of attacks by mountain lions, tigers and leopards:
DO NOT HIKE ALONE: Go in groups, with adults supervising children.
KEEP CHILDREN CLOSE TO YOU: Observations of captured wild mountain lions reveal that the animals seem especially drawn to children. Keep children within your sight at all times.
DO NOT APPROACH A LION: Most mountain lions will try to avoid a confrontation. Give them a way to escape.
DO NOT RUN FROM A LION: Running may stimulate a mountain lion's instinct to chase. Instead, stand and face the animal. Make eye contact. If you have small children with you, pick them up if possible so they don't panic and run. Although it may be awkward, pick them up without bending over or turning away from the mountain lion.
DO NOT CROUCH DOWN OR BEND OVER: In Nepal, a researcher studying tigers and leopards watched the big cats kill cattle and domestic water buffalo while ignoring humans standing nearby. He surmised that a human standing up is just not the right shape for a cat's prey. On the other hand, a person squatting or bending over looks a lot like a four-legged prey animal. If you're in mountain lion country, avoid squatting, crouching or bending over, even when picking up children.
DO ALL YOU CAN TO APPEAR LARGER: Raise your arms. Open your jacket if you are wearing one. Again, pick up small children. Throw stones, branches, or whatever you can reach without crouching or turning your back. Wave your arms slowly and speak firmly in a loud voice. The idea is to convince the mountain lion that you are not prey and that you may be a danger to it.
FIGHT BACK IF ATTACKED: A hiker in Southern California used a rock to fend off a mountain lion that was attacking his son. Others have fought back successfully with sticks, caps, jackets, garden tools and their bare hands. Since a mountain lion usually tries to bite the head or neck, try to remain standing and face the attacking animal.
In an innovative program, Point Reyes National Seashore scientists are collecting data on the populations of reptiles, amphibians and animals in the park. The basic survey unit is a y-shaped array, about 100 feet across, comprising buckets, wire mesh cylinders, aluminum boxes and wooden boards which, in various ways, trap animals without injuring them. Eight sites in the park each have four arrays and a camera that automatically takes a picture when a light beam is interrupted. This is how the mountain lion picture was obtained. By having the same series of arrays at different locations, researchers can compare animal populations. With information collected over many years it is possible to obtain accurate data on the status of a large area. Thus park managers can base conservation efforts on real facts.
Egrets and Herons
Picking their way along the edges of Tomales Bay, the elegant long legged great blue heron and great egret are a dramatic and not too rare sight in West Marin. Their major nesting site in the area is Audubon Canyon Ranch, on Bolinas Lagoon. These birds will travel up to 14 miles to forage so their feeding grounds include Tomales Bay, the Limantour estuary, Abbotts Lagoon and Nicasio Reservoir.
Walking down to Limantour Beach one day, I stopped to watch a great blue heron wading in the wetlands beside the path. Suddenly the heron darted towards the water. It straightened itself and in its beak dangled a small snake. It hung precariously for a while and then became the heron’s next meal. I could see the slow progress of the snake winding down the heron’s long neck. It was a remarkable achievement.
The breeding cycle of great blue herons and great egrets can be broken roughly into four-week segments. Eggs are incubated for four weeks. The young chicks are guarded or brooded, by either parent, for four weeks. The chicks, then quite voracious, can protect themselves fairly well against marauding ravens and other predators, so both parents are free to go out and forage. After a further four weeks the nestlings begin to fly and four weeks later they are independent. The parents fly off while the young generally stay in the nesting area for a while until perhaps they realize their parents are not going to come back and then they too fly away.
Pelicans
Long single lines of low flying brown pelicans skimming the waves are a wonderful sight in May. That’s when they return to Point Reyes after breeding in mid-winter on the Channel Islands and offshore islands in the Sea of Cortez. The American white pelican, which breeds on islands on landlocked lakes of the North American West, heads to Point Reyes in August, usually staying here until January.
Brown and white pelicans have distinctive hunting styles.
The brown pelican hunts independently, catching fish by “dive bombing” their victims. White pelicans work as a group in the shallow waters of a bay, lake or estuary. They surround a school of fish until it is concentrated into a small area and then scoop up their prey in their huge bills.
Both species of pelican were badly affected by DDT. The Californian population of brown pelican declined by 90 percent and it was classified as endangered in 1971. Since DDT was banned in this country in 1972, the numbers of both species have rebounded.
Elephant Seals
After an absence of more than 150 years, the Northern elephant seals have returned to the shores of Point Reyes in increasing numbers since 1981. They have established colonies at the northern end of Drakes Beach and on the shores below the Point Reyes Headlands.
Elephant seals are prodigious long-distance swimmers. The males make the journey from Alaska to California twice a year. Bulls, females and weaners (or juveniles) travel independently. The cows give birth at Point Reyes during winter after a gestation period of 9 to 10 months. Pups are weaned after a month and the cows leave for the open ocean. The pups stay a month longer and then they too go to sea. They and the cows return at the end of spring to molt and then go back to sea to eat. The bulls meanwhile leave in March, travel to Alaska and return in June and July to molt.
The elephant seals all return to the Pacific coast in the late fall and winter to begin the cycle once more. Not much is known of their eating habits as they dive up to a mile deep for their food. They can stay under water for almost two hours. They rely on a thick layer of subcutaneous fat for insulation and use this fat for energy when fasting onshore for long periods. It was this fat that almost caused them to be hunted to extinction in the 1800s. A bull elephant seal could yield nearly 25 gallons of heating oil.
Richard and I were escorted by Ranger Dawn Adams to photograph the elephant seals, as great care has to be taken when approaching a colony to avoid disturbing them. The males can weigh up to 5,000 pounds and reach 16 feet in length. The male proboscis or snout is used to trumpet. The alpha male usually makes the deepest sounds. Perhaps even more impressive than their physical presence was the harmony of sounds the colony made — high notes of the pups, usually mellow tones of the females and then the bass of the males. The alpha male trumpets to warn off other males who might be moving in on his harem. If a male is approaching a cow, she will make a noise indicating whether she is receptive to mating. Sometimes a young male with a small proboscis will sneak in among the females and try to copulate. An alpha male remains the king pin for one to two years. The bulls reach their peak at 9 years and generally live about 15 years. The females begin breeding at 3 to 4 years old. They usually live longer than the bulls.The oldest known age of a female at Point Reyes Headlands was 21 years.
Source: Dr. Sarah Allen, Senior Science Advisor, Point Reyes National Seashore.
The Coho Salmon Run
Our house-sitting saga is perhaps hard to beat. We advertised in the local newspaper, the Point Reyes Light, for a house to rent or housesit while we were rebuilding our house after the Mount Vision fire. We were offered a 30-room farm house in Woodacre which had been built in 1903. It was on the market and needed a caretaker. San Geronimo Creek runs across one end of the property and we were very happy to oblige.
One morning we saw some people standing on “our bridge.” We thought they were teenagers and prepared to give them the big lecture. On closer inspection (the driveway is rather long) we realized they were “responsible adults” who, when I said they would need to see the house with a realtor, replied they were looking at the salmon. There were indeed five salmon swimming up the creek. They had made their way up a stream which at times is only a couple of feet wide, in other places just a few inches deep. They used their tails to move themselves up the shallow parts, seeking a predetermined destination.
Scientists think the chemistry of the stream is implanted in the coho at birth. As adult fish, they swim in the ocean and can detect the taste of the freshwater streams merging with the seawater. When they are three years old, they know they need to return to their particular stream to spawn. Their taste is not infallible, some salmon will choose a different stream or tributary, particularly if the water is turgid. Despite what I learned from the scientists, I could not help think that perhaps the salmon were choosing the small streams for spawning in order to give their young a safe sanctuary.
We watched the coho for hours. Occasionally there was great activity as four or five salmon swam up and over each other, splashing and jostling, the males trying to keep others away from their chosen female. Females lay between 2500 and 3000 eggs. They do not put “all their eggs in one basket,” choosing instead to build several nests, or redds, by swimming on their side and digging a trench in the sand. The eggs will be fertilized almost immediately by a male, who discharges millions of spawn or milt over the eggs. Sometimes the eggs are fertilized by different males. There is usually a 98% success rate for fertilization.
It takes about 50 days for a coho egg to hatch in a stream with a temperature of 50 degrees fahrenheit, less time if the water is warmer. The salmon fry lives in the stream for a year, and then when it is four or five inches long, it swims to the ocean.
The coho lead short, perilous lives. The streams may dry up, leaving them either stranded or prey to birds; they can be eaten by seals or sea lions or caught by fishermen; although they usually keep to the western side of the Pacific, they have been known to swim to the Asiatic coast and back in their two year-sojourn in the sea. As the females enter their chosen stream, the different chemistry of fresh water starts the maturing process of the eggs. The female then races against her biological clock to reach the place where she wants to lay her eggs.
Even in the hatcheries, only half a percent of the fertilized eggs reach maturity. The coho give their all for their young. Days after spawning, both male and female die.The amount of time they have to enjoy their place of birth depends on the distance upstream they have swum. In West Marin, where they swim about 25 miles upstream, they might live five days after spawning. In areas where they have traveled 100 miles in fresh water to spawn, they will have exhausted all their reserves and will survive only a few hours. We saw a vulture take a dead salmon out of the water. It did not take the natural world long to recycle.
If there are heavy rains after the spawning, there is a danger that the movement of silt will smother the eggs which have to be constantly breathing in oxygen. More rarely, heavy flooding can wash away the stream bed and its redds.
Coho have been declared a threatened species from Fort Bragg to Santa Cruz. This requires that the Federal Government oversee a restoration program of the habitat of the coho. As the logging companies are responsible for most of the silt in the streams, the classification of the coho as threatened has wide-reaching repercussions.
Native Deer and Doc Ottinger’s Exotics
An excursion to the Point Reyes National Seashore almost guarantees the sighting of deer. Native to the area is the black tailed or “mule” deer. In the 1940’s and 50’s Doc Ottinger imported axis and fallow deer for hunting.
The axis deer comes from India while the fallow deer is indigenous to the Mediterranean region of Europe and Asia Minor. Most of the imported fallow deer were pure white so they would be easy to hunt. However these deer also are brown, black and mixed. Both exotics are commonly seen near Bear Valley, sometimes even in the same herd, though there is no evidence of interbreeding.
© copyright Kathleen Goodwin
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