Thursday, July 31, 2008

Coexisting With Wildlife

The Puente Hills is surrounded by a large perimeter of urban edge (approximately 25 miles). This presents challenges to people living near or adjacent to the natural areas, as well to the plants and animals that occupy the open space. On the urban side of the urban/wildland interface, people living adjacent to natural areas often experience visits from wildlife. The smaller wildlife, such as rodents, raccoons, and skunks often go unnoticed; whereas larger mammals such as coyotes draw the attention of humans. This is not something that should alarm people, but instead should make people aware.

The Habitat Authority periodically receives calls from residents encountering coyotes and other wildlife, including neighborhoods that are more than a mile away from the Puente Hills open space. This morning we received a call about a coyote that was walking down a residential street in Whittier more than a mile from the nearest natural area. Coyotes are one of the most adaptable animals, occupying virtually every habitat type in North America, including urban areas. As with many other types of wildlife, coyotes are more commonly out from dusk to dawn, moving through urban areas along railroad tracks, greenways, parks, and drainage facilities. However, encounters do occur during the day.

Occasionally, people will experience a more personal encounter with a coyote, including the loss of pets, and very rarely an attack on humans. However, people should not be fearful of coyotes. Coyotes play an important role in the ecosystem, helping to keep populations of rodents (rats and mice) and other small mammals under control. Naturally coyotes are fearful of humans, however coyotes readily lose their fear of humans when people intentionally (or unintentionally) provide food/water or shelter for them, or otherwise do not try to deter them from visiting. It is not feasible to completely eliminate coyotes, but removing sources that attract coyotes can go a long way to avoiding a conflict.

It is unfortunate when a person loses a pet to a coyote, and this may elicit a very emotionally negative response from the pet owner towards coyotes in general. However, the coyote views the pet as one of many food sources, and this type of encounter is almost always preventable. People that live in areas with coyotes should not leave their pets outside at night. If a pet cannot be brought inside, then the pet should be kept in some type of an enclosure that other wildlife cannot get in to. In areas where the occurrence of coyotes is much higher, pets (especially smaller dogs and cats) should ideally be placed outside only while being supervised, even possibly during the day. For areas where coyotes are attacking pets, there should be a heightened awareness towards this behavior, and if necessary the appropriate wildlife authorities can be notified. Local authorities may investigate these occurrences, but they may not actively trap and remove coyotes simply in response to attacks on pets.

The presence of unwanted wildlife in urban neighborhoods (especially in yards) is often due to one or more factors caused by the residents themselves, in some instances knowingly. As noted above, the presence of small pets left outside is a big attraction for coyotes as a food source. Other things that attract coyotes include pet food that is left outside; unsecured garbage cans; ripened fruit that has fallen off of trees; shelter such as dense shrubbery; and water sources such as pet bowls, fountains, ponds, and swimming pools. It may be difficult to remove all attractants (such as ponds and swimming pools), however at the very least people should not provide food to coyotes or any other type of wildlife. Besides it being a bad idea ecologically, it is against the law to feed or otherwise provide food to specific types of wildlife. This includes ground squirrels, coyotes, raccoons, skunks, and opossums; all of which are common in urban areas.

As noted above, coyote attacks on humans are rare. Of those attacks that have occurred to humans, a significant number of the attacks have been towards small children. Coyotes can view small children as prey animals (particularly when a child is crouched down while playing). Particularly in areas with a higher occurrence of coyotes, children should be supervised by an adult at all times while outside. If you are approached by a coyote, or even if you see one in your yard, every effort should be made to frighten the coyote away and make the coyote fearful of humans. Make yourself as big as possible by raising your arms. Make loud noises to startle the coyote. Spray the coyote with water if a hose is available. If the coyote still will not leave, then throw an object such as a rock as near the coyote as possible but not at its body. If this still does not work, then throw an object at the body, though not at its head.

If a coyote does not retreat after trying all feasible measures, if a coyote bites a human, or if one otherwise truly acts aggressively, then the appropriate wildlife authorities (including Animal Control) should be contacted immediately. If necessary and feasible, then the appropriate authorities may determine that elimination of a coyote is warranted. Simply seeing a coyote in a residential area is not a reason to be alarmed, and does not justify removal, however it should make people aware that coyotes are present, and what can be done to reduce the likelihood of a closer encounter. Also, there is a difference between a coyote that is being bold and one that is acting aggressively. A coyote coming into a yard looking for food is acting boldly, but is not necessarily exhibiting aggressive behavior towards humans. The difference between bold and aggressive may be a fine line at times, but people should be aware that the sheer presence of a coyote is not a cause to call for its removal, especially for people living very near to natural areas. Coyotes that have become bolder have done so by losing their fear of humans. Even though a bold coyote may not be a cause for removal, its reasons for being bold should be addressed. Do not simply ignore a bold coyote.

There are many resources available for information and guidance on coyotes and other wildlife. Please visit our website (http://www.habitatauthority.org/) for more information on coexisting with wildlife. In addition, the websites of the California Department of Fish and Game, and many other agencies and organizations provides valuable information. If you are interested in a DVD on coexisting with wildlife or other literature, please contact the Habitat Authority at (562) 945-9003. A ranger or other staff member would be pleased to personally visit people with questions or concerns, or alternatively we could mail materials to you.

Friday, July 18, 2008

Red skimmer

Yesterday I photographed this red skimmer dragonfly in Sycamore Canyon. Dragonflies and the closely related damselflies are highly beneficial predatory insects. They are responsible for eliminating large numbers of mosquitoes, as well as other pesky insects. Dragonflies such as the red skimmer are very specialized hunters. They have large compound eyes for spotting their prey, and sharp mouthparts for cutting up insect prey. Dragonflies are skilled at maneuvering through the air, as a result of their four powerful wings that move independently. This allows dragonflies to move both forward and backward. Their legs are not suitable for walking, but instead are used to hold their insect prey that is captured during flight.

Dragonflies and damselflies are strongly tied to aquatic environments. Their larval stage (referred to as naiads) develop in the water. The naiads themselves are aquatic predators, capturing things that include insects, tadpoles, worms, and small fish. Worldwide there are 5,000 known species of dragonflies and damselflies, with approximately 450 occurring in North America.

Wednesday, July 2, 2008

Poison oak and pistachios.....it's all relative.

I am a botanist by education (and work experience), and so I have always enjoyed studying the relationship of one plant to another. In trying to get non-botanists to be interested in plants, a great teaching tool is to relate plants commonly used by people (food, landscaping, etc.) to native plants that one will see in natural areas. Poison oak is a great example. Hopefully those of you that are frequent enough visitors to the Puente Hills and other natural areas will recognize the attached photo as the oily, reaction-causing leaves of poison oak (leaves of three…leave it be!).

Here is a bit of background on plant taxonomy.....two closely related species of plants occur in the same genus (genera). For example, white sage, black sage, and purple sage are all in the genus Salvia. Similarly related genera are placed in the same plant family. Plants of the genus Salvia, along with other “mints”, are placed in the plant family “Lamiaceae”. Getting back to poison oak....this plant is placed in the family “Anacardiaceae”. Other representatives of this family that occur in the Puente Hills include native plants such as lemonadeberry, laurel sumac, and skunkbrush, and non-native plants such as the Peruvian pepper tree. Many species in this plant family contain a type of oil called “urushiol”, which is particularly abundant in poison oak (genus Toxicodendron). This is the oil, which for people that are sensitized to, will cause the characteristic delayed allergic reaction. Up to 30% of people have no allergic reaction when in contact with the oils from poison oak; however most will become sensitized to it with repeated exposure.

What many people find interesting is to know what common food items occur in the same plant family, and are therefore more closely related to poison oak. These include the pistachio, cashew, and mango. The urushiol oil is found in the nut shell of the cashew fruit (though not in the cashew fruit itself), and in the mango plant sap as well as the skin of the mango fruit. With the respect to the mango plant, breaking the vine of a green mango fruit will produce a fine aerosol of sap that causes severe reactions in previously sensitized individuals. The mango fruit skin has a lesser concentration of urushiol, though still with some potential for the delayed skin rash with more sensitive people. However, the edible part of the mango fruit itself does not cause these reactions, and is one of the most popularly used fruits worldwide; used for food, juice, flavoring, fragrance, and color. The mango is an excellent overall nutrient source, including dietary fiber, carbohydrates, and antioxidant vitamins.

Here is a great game to play. The next time you are eating a meal, think about each plant product that you are eating, where it comes from, and what it might be related to. Is it a fruit? If not, what part of the plant does it come from? Is it a root? A stem? A leaf? Dinner will never be the same again!

Thursday, June 26, 2008

The Puente Hills are a beautiful place….so let’s keep it that way!

One of the great perks of my position with the Habitat Authority is being able to explore the various trails of the Puente Hills. These hills are a great resource to people, and will remain that way as long as that resource is respected and people act responsibly. A few weeks ago I was hiking the Coyote and Ahwingna Trails in the Hacienda Hills and I came across multiple acts of vandalism. Unfortunately it is all too common to find our trail signs and other structures sprayed with paint. As bad as that is, at least those things are relatively easy to replace or cover up. However, the acts of vandalism that I witnessed were to trees and shrubs, including tagging all over the trunks of several oak trees. What was once a beautiful tree is now lost forever.

For anyone that hikes, bikes, and rides horses in the hills, please report any acts of vandalism that you witness in progress. Do not make any effort to approach individuals or try to stop them. However, you can call our emergency number at (562) 698-1446 anytime to report people in the act of vandalizing, or any other illegal activity on Habitat Authority lands. Please help us to keep the hills beautiful. Thank you!

Friday, June 20, 2008

Why do we restore habitats?

One of the major aspects of the Habitat Authority’s management of open space in the Puente/Whittier Hills is the restoration of degraded habitats. The term "habitat restoration" refers to the process of restoring the functional aspects of a given ecosystem to a semblance of its pre-disturbed state. As a result of more than 100 years of human land use, the majority of the Puente Hills contains disturbed habitats, including those dominated by non-native vegetation. Past and ongoing land uses that have created or contributed to disturbed, altered habitats include livestock grazing, development, oil extraction, the intentional planting of non-native vegetation, and the use of non-native invasive vegetation on properties adjacent to open space where invasive plants spread into natural areas. The Habitat Authority actively restores degraded areas by removing non-native vegetation (such as non-native grasses, mustard, thistle, castor bean, tree tobacco, etc.) and planting native vegetation that would have been present prior to the disturbance.

Approximately 190 acres of Habitat Authority lands have been or are currently being restored in some manner, including 130 acres initiated by the Habitat Authority, and another 60 acres of mitigation conducted on Habitat Authority lands to mitigate for local development projects. Restoration projects include coastal sage scrub and sycamore riparian habitats at the Hacienda Trailhead; riparian restoration in Sycamore Canyon; coastal sage scrub restoration on the former Unocal property (east of Colima Road); coastal sage scrub restoration near the Hellman Trailhead; the restoration of coastal sage scrub at the Arroyo Pescadero Trailhead; and the restoration of oak and walnut woodland, coastal sage scrub, native grassland, and riparian habitats in Powder Canyon.

Though it makes us feel good to be a part of successful restoration projects, that feeling is a byproduct of the broader goal….to improve the overall the health of the ecosystem. Through the restoration of degraded habitats, the Habitat Authority and other participants have created (and continue to create) native habitats offering shelter and food for wildlife that otherwise would not exist in the degraded habitat. For example, the federally listed coastal California gnatcatcher is nesting in coastal sage scrub vegetation at the former Unocal property where the patch of habitat did not exist just two to three years ago. Gnatcatchers have occupied that property in the past, but we have expanded the habitat to allow for the establishment of new territories and the growth of the gnatcatcher population. Besides rare species, we are providing habitat for all sorts of mammals, birds, reptiles, amphibians, and invertebrates.

Earlier this week I visited our former Diaz property on the far eastern edge of the preserve near Harbor Boulevard. Five years ago this property contained a house and other structures, an avocado orchard, and countless more non-native vegetation. Since then we have restored nearly 25 acres to coastal sage scrub and oak/walnut woodland. During my visit the other day, I came across a family of mule deer that are regular residents of the property. As I walked through the site, I was treated with the appearance of two fawns that calmly walked out from the shelter of a grove of walnuts (see photo above). It is rewarding to know that the habitat was restored for them.

Friday, June 13, 2008

Just finished a hike? Time for a tick check!

Just a reminder that when you are spending time outdoors in natural areas, you should periodically check yourself for ticks. Ticks are small parasitic arachnids that live on the blood of their hosts, which include mammals and birds. More importantly, ticks can carry a number of diseases, including Lyme disease. All ticks have three different life stages (larval, nymph, and adult), though only the nymph and adult stages are of concern for transmitting diseases. The adult stage is the most common that people hiking on trails in the Puente Hills may be exposed to. Adults find their hosts by hanging onto the tips of shrubs, grasses, etc. while waiting for an unsuspecting animal (such as yourself) to come along. Ticks don’t jump or fly, they simply grab on as you pass by. The smaller nymphs (about the size of a poppy seed) live within leaf litter on the ground. Because of their smaller size, the nymphs are the most difficult to detect, though a person would be far less likely to pick one up if only hiking a trail.

There are many different kinds of ticks in California, with two of the more common ticks being the black-legged tick and Pacific Coast tick. In California, the black-legged tick is the only one known to transmit Lyme disease, although ticks in general can carry other diseases such as Rocky Mountain spotted fever. Found elsewhere in the United States, the other carrier of Lyme disease is the deer tick. Most sources report that on average, 1 to 2 percent of adult black-legged ticks are infected with Lyme disease, as opposed to 2 to 15% of nymph ticks, though the percentage can be much greater in higher risk areas such as northwestern California and the northeastern United States. In addition, with infected ticks the risk of transmission increases the longer that the tick is attached. Therefore, it is important to regularly check yourself for ticks while outdoors in areas where ticks can be found, and also give yourself a very thorough check when you return home.

Don’t let the potential for ticks keep you from getting outdoors. There are many things that you can do to reduce your risk of getting bitten by a tick.

  • Dress appropriately. Wear light-colored clothing so that you can spot ticks easily. Wear full-length long pants, long-sleeved shirts, and hats to keep ticks off of your skin and out of your hair.

  • When hiking a trail keep to the middle of the trail and avoid brushing against vegetation (although this is often difficult depending on the trail).

  • Periodically check yourself on the trail for ticks, or better yet have a buddy help you. Ticks may be hiding in the seams of clothing. When are finished with your outdoor activities, give yourself a very thorough tick check, and then once again when you get home. Be sure to check your pets for ticks if you take them outdoors with you.

  • As an added precaution, repellents are available that can be sprayed on your clothing.

If you find a tick attached to you, remove the tick immediately with a pair of tweezers. Research suggests that it takes from hours to one or two days for ticks to begin transmitting disease-causing bacteria. Do not use chemicals, heat or anything else that might irritate the tick and cause it to regurgitate disease-causing agents into your skin. Grasp the tick’s head/mouthparts with a pair of tweezers as close to your skin as possible. Be careful not to squash the tick, as this may force fluids from the tick into your skin. Using the tweezers, slowly and steadily pull the tick straight out. It is important not to leave any mouthparts in your skin, as this could cause a secondary infection. If you are unsure which species of tick that bit you, keep the tick in a plastic bag or vial of alcohol for later identification.

After removing the tick, consult with a physician. Your doctor may prescribe a brief treatment of antibiotics out of precaution. Regardless, if you develop any flu-like symptoms within a few days to weeks of being bit, consult with your doctor. One of the common symptoms of Lyme disease is a characteristic “bulls-eye” rash that develops at the site of the bite, and then later can spread elsewhere. The technical term for this rash is erythema migrans. Other symptoms include headache, fever, fatigue, etc.

In 15 years of being a field biologist, I have literally picked hundreds of ticks off of me, and have probably had 6 or so that have attached, though I have caught them quickly. So, like anything else, the key is to be aware, educated, and responsible. Just add ticks as one more thing to your list of things to watch out for. Make a tick check a part of your regular outdoor routine!

Here is a link to a document from the California Department of Public Health website for more detailed information on ticks and Lyme disease:


http://ww2.cdph.ca.gov/HealthInfo/discond/Documents/Lyme/LymeDisease2008.pdf

Thursday, June 12, 2008

Lizard Boot Camp

Human behavior is an interesting thing. Spending an afternoon watching people in a local shopping mall will give a sociologist/psychologist a wealth of behavior to observe and interpret. The behavior of other animals can be just as fascinating, if not more so if you know what to look and listen for. For those of you that hike in natural areas such as the Puente Hills, there are great opportunities for you to be the amateur animal sociologist.

Just as with humans, the behavior of other animals is used to attract mates, threaten or warn potential adversaries, or just to be social. Individual bird species possess a range of calls for these purposes, from a warbling melodious song, to a harsh rasp. Lizards, on the other hand, use their bodies.

Have you ever seen a lizard doing “pushups” and wondered what that was about? If you have ever come across a lizard, then either you have seen this, or the lizard was doing this but you missed the signal. No, they are not getting exercise like you are, or training for the next “Survivor – Puente Hills”. If you come across a lizard doing pushups (such as the western fence lizard in the above photo), then likely it is doing this in response to you. For various reasons, lizards will do what appear to be pushups, a series of jerky up and down movements with their head and forelimbs. However, depending on the slightest nuance in the way they move, a lizard could be saying anything from “Get off my rock now!” to “Will you be my valentine!?!” In your case, the lizard is probably not trying to select you for a mate, but instead it is warning that you are trespassing on its territory.

So, the next time you want to tell a friend or family member to get out of your favorite chair, try it with body language!