The Many Species of Orphan Care

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By Cambria Wells, Wildlife Technician

California Towhee Fledgling Photo by Brittany Moser

The rest of the world might have four seasons, but wildlife rehabilitation has even more. Busy season at California Wildlife Center begins with the opening of the Orphan Care Unit when squirrel kits, opossum joeys, and dove squabs begin to trickle in. We never know when the moment will strike, but it’s not long before everything changes again.

Oak Titmouse and Western Bluebird Fledglings
Photo by Cambria Wells

At the end of May, we’ve settled firmly into baby bird season, with a wide variety of species residing in Orphan Care and others moving into outdoor enclosures to strengthen their flight and condition for release. Our first songbirds are Northern Mockingbirds, California Towhees, House Finches, and Lesser Goldfinches, common backyard birds here in Southern California that quickly run into trouble with tree trimmers, outdoor cats, and windy day accidents. Next, we begin to see American Crows and Common Ravens, favorites of many CWC volunteers. After these familiar visitors arrive, we can never predict which other species will come in.

In 2017, the Orphan Care Unit was overwhelmed with a flood of young Northern Mockingbirds. In 2018, we provided supportive care to a large number of House Finches. Thus far, 2019 appears to be the season of variety. Orphan Care has already treated a number of species such as the Oak Titmouse, Western Bluebird, Bullock’s Oriole, Dark-eyed Junco, Black-headed Grosbeak, and more. Each of these species requires different care, from the unique nesting needs of Cliff Swallows and Wrens to the particular eating habits of Towhees and Bushtits. Some also enter into care with gastrointestinal parasites or wounds which require medical treatment. Volunteers and staff work each day to provide these birds the nutrition and stimulation they require, rapidly adapting to changing circumstances and patients.

Bushtit Fledgling
Photo by Brittany Moser

Black-Headed Grosbeak Fledgling
Photo by Cambria Wells

Over one weekend, the Orphan Care room can change completely, and your favorite patient can go from a nestling to a fledgling seemingly right before your eyes. In the two weeks a patient spends conditioning for release in an outdoor enclosure, they become completely independent, and their releases are a bittersweet victory. As each round of young animals moves on, we turn to the next and alter care to meet their needs again. The precious privilege of being involved in the early life of orphaned wildlife is only outweighed by knowing release means they’ll have a chance to raise their own young someday, in the wild, where they belong.

Red-Shouldered Hawk with Anticoagulant Rodenticide Toxicosis

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By Dr. Stephany Lewis, Veterinarian

This winter, CWC admitted an adult male Red-Shouldered

Red-Shouldered Hawk
Photo by Johanna Molina

Hawk after he was found on the ground in Santa Monica, too weak to fly. On physical examination, his only injury was a very small laceration on his toe, only about 5 mm in length, yet his feathers were completely soaked with blood and the laceration was actively bleeding. The mucous membranes in his mouth were pale white, and he was so weak that he couldn’t stand, wouldn’t open his eyes, and was barely responsive to external stimuli. A small amount of blood was collected from the bird for some basic bloodwork. He was found to be severely anemic, with 5 times less red blood cells than normal.

Sadly, those of us working in wildlife rehabilitation know that there is only one thing that could cause these clinical signs in a bird of prey. This bird was suffering from anticoagulant rodenticide toxicosis. Anticoagulant rodenticides are rat poisons that cause death to rodents by preventing their ability to clot their blood. Non-target species, such as Hawks, Owls, Bobcats, Coyotes, and Mountain Lions are exposed to these compounds by ingesting the rodents that have eaten these poisons. The poisons do not kill the rodents immediately, but rather slowly weaken them and make them easier prey. Some of these compounds, such as brodifacoum, difethialone, and bromadiolone, are known as “second generation anticoagulant rodenticides”. These compounds were invented in the 1970s in response to rodents becoming resistant to the “first generation” compounds, such as warfarin. One of the differences between the first and second generation rodenticides is also what makes the second generation compounds so much more dangerous for wildlife; they last for a very long time in the body. This means that non-target wildlife species can ingest multiple small doses over long periods of time until they build up levels high enough that they are no longer able to clot their blood. This has disastrous consequences. Animals can bleed into their lungs, causing severe distress, as well as into their brains, eyes, joints, and muscles, causing severe pain and permanent disabilities. Or, like our Red-Shouldered Hawk patient, they can lose all of their blood through what should be an inconsequential wound. Additionally, Bobcats and Mountain Lions are believed to suffer deleterious impact on their immune systems due to chronic exposure to these poisons, making them more susceptible to illness and death from infectious diseases such as mange.

Luckily for our Red-Shouldered Hawk patient, there is an antidote to these poisons, and it is just a simple vitamin, vitamin K. This treatment needs to be given daily for four weeks. Additionally, he received fluid therapy for the first week (a blood transfusion would be the preferred treatment but is unfortunately not an option for our unique patients). This bird actually had a catheter placed into a bone in his wing to quickly replenish blood volume and blood pressure after such drastic blood loss.

Forty-three days after he arrived, our Red-Shouldered Hawk had normal bloodwork, was well-conditioned, flying beautifully in one of our flight pens, and ready to be released! This was a wonderful outcome for this patient, but sadly most of the rodenticide victims who come to us are not as lucky. Because they arrive very late in the course of their illness, the majority of them pass away in the first 24 hours, before our vitamin K therapy has had time to work. Every patient who passes away due to rat poison is submitted for examination by biologists at the California Department of Fish and Wildlife to confirm the cause of death and aid research proving how damaging these poisons are to our native wildlife. The exposure frequency of wildlife to these compounds continues to be astounding, despite previous legislation made to limit their use. Scientists continue to detect these compounds in anywhere from 79 to 100% of animals tested, and in many cases, 3 – 6 different compounds are detected in the same individual.

Anticoagulant rodenticides pose a substantial and far-reaching threat to wildlife and ecosystem health. A California bill, AB1788, has reached the State Senate, and if passed will greatly restrict use of these poisons in our state. CWC is so grateful for everyone who has been working tirelessly to get this bill passed, and we hope you join us in urging your senator to pass this important legislation! Our wildlife deserves poison-free food!

Treating a Parliament of Owls

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By Cambria Wells, Wildlife Technician

This Long-Eared Owl suffered a wing fracture
Photo by Samantha Orzech

 

It’s the beginning of Owl breeding season, and the intensive care unit is

packed with an assortment of these special birds. Owls are among CWC’s most diverse patients; they encompass some of our largest and smallest raptor patients, come from a dramatic range of habitats and circumstances, and have some of the new year’s most impressive recovery stories.

A Long-Eared Owl rescued in Malibu this past December has just moved to an outdoor enclosure for conditioning. He was injured while overwintering in our area. The soft tissue damage around his wing fracture meant that his prognosis was guarded, but two months and several surgeries later he is flying with confidence and nearly ready to return to the wild. This Long-Eared Owl and a Western Screech-Owl, both current CWC patients, had part of an eye removed this month. Thanks to their highly sensitive hearing, these birds are adjusting well and will still be able to thrive and hunt in the wild upon release.

Barn Owl 19-62 arrived with a broken leg
Photo by Cambria Wells

Another CWC Owl patient, a Barn Owl, was admitted after the recent storms with two fractures to the tarsometatarsus bone in her lower leg. She was very wet and dirty from being found on the side of the road, leaving her weak and unable to thermoregulate. Her unstable condition and the proximity of the fracture to a joint made her surgery difficult, but thanks to Dr. Stephany Lewis’ work in pinning her bone she now has a brighter future ahead.

Our Owl patients display their will and vivacity by surviving head trauma, serious fractures, secondary poisoning and more. Currently, we are experiencing an influx of injured Owls as they compete for breeding partners. We will see another wave when orphaned Owlets begin to arrive in early March, and when juvenile Owls run into trouble after leaving their parents later this summer. Every one of these patients, and their healthy cousins beyond our walls, deserve all the care, conservation, and respect that we can offer as they live out their wild lives around us.

Mockingbirds: Masters of Mimicry, with just a Note of Mystery!

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By Melissa Hartman

CWC sees many fledgling mockingbirds each year Photo by Jamie Pelayo

 

Mockingbirds sing one heckuva lot. You can hear them all year long, at

any time of the day, compiling sequences of repeated phrases, including riffs on calls made by other bird species. Like other songbirds, Mockingbirds’ songs are used mainly for courting or to defend territory.

Weighing in at a measly two ounces, a male Northern Mockingbird can produce several hundred phrases, picking up notes acoustically comparable to their own cadence and tone, including calls of other birds such as Jays, Hawks, Orioles, Robins and many others, as well as non-avian impersonations of dogs, cats, frogs—and even car alarms, cell phones and police sirens! They’re not called by their scientific name, Mimus polyglottos—”mimic of many tongues”—for nuthin’.

The Northern Mockingbird is one of 14+ Mockingbird species, many of which “mock,” but why? Some bird species imitate others to frighten their neighbors and steal their food; however, scientists have noted no change in behavior in birds imitated by Mockingbirds. Birds also are known to copy songs as a courtship strategy, but leading bird behaviorists cannot conclusively point to this as a hypothesis for why exactly Mockingbirds mock.

Last year at California Wildlife Center, Northern Mockingbirds were ninth of the ten most frequent species of the 4,300 animal patients seen. We took in 122 for a number of reasons: caught by cats, attacked by raccoons, with broken limbs, injured in window-strikes, orphaned.

As a CWC patient, the Northern Mockingbird is talkative and curious. It’s a pleasure to care for and release them to continue their amazing vocalizing in the wild!

 

Meet Patient 1311: A Comprehensive Care Success Story

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by Jennifer Brent, Executive Director

You have heard their calls and seen them soaring high above the oak forest here in Southern California. These hawks are common across North America, though those found in California tend to be redder than elsewhere.

It’s only seven months into 2018, and it seems likely that the year is going to bring us an unprecedented number of Red-shouldered Hawks. So far, we have seen 12 of these majestic patients, in comparison to the last two years’ numbers of 15 and 17 admissions.

On May 7, Patient 1311, a Red-shouldered Hawk unable to fly, was recovered—literally–on Van Nuys Boulevard in Pacoima and brought to the East Valley Animal Care Center, where one of our volunteers picked her up. Upon arrival, staff veterinarian Dr. Stephany Lewis determined that the bird had suffered a left midshaft major and minor carpometacarpal fracture (in humans, a break near the wrist, where it meets the hand on the thumb side). At just 436 grams (slightly less than one pound), she was also underweight.

The next day, she was given pain medication and splinted. A few days later, she was anesthetized so that the area could be cleaned and the broken bones pinned, and she was given more analgesics and antibiotics. On CWC’s use of pharmacology in birds, Dr. Lewis states, “Our avian patients are placed on many of the same medications that are prescribed to dogs, cats, or even humans. Due to the physiology of birds and their much higher metabolic rate, often the doses are quite different. Dosing medications, particularly pain medications, for the number of species we see here can be a real challenge. This is an active area of study, so we are always trying to stay on top of the latest research.”

In wildlife medicine, we are often called upon to anesthetize animals for exams, because of the incredible stress they experience and for the safety of the handler performing the requisite intensive palpitating. A week after pinning, Director of Animal Care Dr. Duane Tom again anesthetized Patient 1311 for an exam to ensure that the pins were still in place. Three weeks later, because of excellent progress, Dr. Tom again anesthetized her to remove the pins. The wing was then wrapped to continue healing.

The Red-shouldered Hawk continued to recover well, showing good appetite and range of motion. The vets decided that she was ready to move to a lower enclosure that allows for more space and freedom, to begin physical therapy and desensitization to humans. The wing wrap was removed, and she was transferred to a lower enclosure on June 21. There Hawk 1311 was soon seen to fly on her own for the first time since being in our care. Her initial flights showed that she was able to gain good height but was somewhat crooked in flight.

The Red-shouldered Hawk practices her flying. Photos by Paul Simon Needham

On July 13, Diana Mullen, a highly-experienced volunteer who assists us by creancing injured birds, took her out for a test flight. Creancing involves attaching leather straps (jesses) to the bird’s lower legs and then attaching these jesses to a line up to 300 feet in length. Though tethered to the handler, the bird is still able to gain altitude, bank, and land on her own. For birds who have been with us for an extended period of time, these flights prove invaluable to progress, determining any muscle atrophy as well as serving as an assessment of the ability to thrive once released. On her first test, Hawk 1311 flew three times with great symmetry, which boded an excellent prognosis. The next day, Diana again flew her; she continued to make excellent progress.

Because of some damage to the feathers during surgery and while the wing wrap was in place, Hawk 1311 became a candidate for imping, the surgical replacement of damaged or missing feathers with healthy ones; this allows for release while new feathers grow in.

While all these measures taken together might seem rather extreme, they are fairly standard for a raptor that comes to California Wildlife Center with an injury of this type. In our years of experience, we have learned that comprehensive care from exams, surgery, rehabilitation and physical therapy ensures the best chance of a successful return to the wild.

Everything You Ever Wanted to Know about Mourning Doves (but Maybe Never Thought to Ask)

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by Melissa Hartman, Administrative Assistant

CWC treats many fledgling Mourning Doves. Photo by Jamie Pelayo

So far this year at California Wildlife Center, Mourning Doves are the second most common species seen. Exceeded only by the number of Mallard Ducks admitted, Mourning Doves make up 13% of all our animal patients.

If the world can be divided into those who consider this seemingly ubiquitous bird with its estimated US population of more than 400 million to be too prevalent, too present, too ordinaire to be worth much attention and those who find them interesting, this writer has recently migrated from the former to the latter group. Not only are they interesting, but also rather charming and even downright funny:

They’re Interesting…

The Coooo-OOOOH-woo-woo-woo cry that seems soooo mournful is actually a come-hither mating call made almost always by males.

Weighing in at a measly three to six ounces—get this—Mourning Doves have been clocked at 55 mph! As a figure of comparison, the Northern Flicker, at a similar weight, flies at 23 mph.

Unlike most birds that tend to gulp water and then rotate their heads, using gravity to bring it down their throats, Doves sip water. Their diet, composed mostly of hard, dry seeds, necessitates consumption of significantly greater quantities of water than many other birds. Birds are typically more vulnerable to predators when drinking water. Sipping is thus a form of risk-management.

And Charming…

Mourning doves remain with the same mate all breeding season long, and pairs tend to mate for life.

Mourning Dove dads do their share. On the nest, they incubate from mid-morning to mid-afternoon, while moms take over in the evening, going through the night. Males and females work together to feed their babies.

And Funny!

How the Mourning Dove became a symbol of peace is kind of a head-scratcher. Notice how other birds in the feeder keep their distance? Yep, they know if they get too close, they are in for one HECK of a pounding! Doves crouch low, ready to go the distance, scratching, biting with their beaks, even battering with their wings in a move called…boxing!

The Mourning Dove is a most engaging CWC patient. It’s our pleasure to care for them and return them to their wild home!

A Red-Tailed Hawk Flies Free after Bone Fracture

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By Dr. Stephany Lewis, DVM, Veterinarian

This Red-Tailed Hawk suffered a coracoid fracture afterbeing hit by a car
Photo by Heather Patrice Brown

This adult male Red-Tailed Hawk came to us from West Hollywood on February 10th. He was found on the street, unable to fly, most likely after having been hit by a car. Just like every patient in our care, he received a full physical exam, and radiographs (x-rays) were taken. He was found to have some mild trauma to his left eye, as well as a fractured left coracoid bone, a bone in the shoulder of birds that helps stabilize the shoulder while in flight. When this bone is fractured, birds are unable to get any lift, and thus are left unable to fly. Luckily for this Hawk, this bone usually heals very well without surgery.

We bandaged the bird’s wing to his body for about three weeks so that the bone could become stable enough to heal. He received pain and anti-inflamatory medications during his treatment, as well as physical therapy to stretch the wing. After time spent in our flight pens, becoming stronger on his own, his flight was deemed strong enough for release. Our patient was brought to a park close to the location he was found and took flight straight out of his box–right into the treetops!

Johanna Molina, Wildlife Technician, places a wing and bodywrap to allow the bone to heal
Photo by Heather Patrice Brown

Electrolytes prevent dehydration
Photo by Heather Patrice Brown

The Red-Tailed Hawk flew off upon release
Phot by Luke Stebick

 

Orphan Care Unit Update

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By Jennifer Guess, Senior Wildlife Technician

Orphaned Fox Squirrels need to be fed frequently
Photo by Anne Slattery

It’s finally spring and the Orphan Care Unit (OCU) at California Wildlife Center is up and running! The doors officially opened for the season on March 15th. Of course, nature had its own plans.The first orphaned patient California Wildlife Center received in 2018 was a nestling Band-Tailed Pigeon on January 25th. Between then and March 15th, CWC received 95 orphaned animals who were treated in the Intensive Care Unit until OCU opened for the season. Forty-six of those young patients were Eastern Fox Squirrels being cared for under the supervision of our home care rehabber Glenn Ellis. Besides orphaned Eastern Fox Squirrels, CWC received 22 Mourning Doves, 13 Band-Tailed Pigeons, nine Virginia Opossums, and five Hummingbirds.

Fledgling birds like this Northern Mockingbird learn to fly from the ground up
Photo by Jamie Pelayo

As of this writing, the OCU has taken in over 275 young patients. Our dedicated team of volunteers, staff, and our Homecare Network have been looking after more than 105 Eastern Fox Squirrels, 75 Virginia Opossums, and 90 baby birds including House Finches, Lesser Goldfinches, Northern Mockingbirds, Hummingbirds, Mourning Doves, and Band-Tailed Pigeons. As time progresses, the mammals in OCU will slowly transition into outdoor enclosures preparing for release. We will see a major influx of injured and orphaned baby birds.

If you find a young animal the first thing you will want to do is look from afar to see if it has any obvious injuries. If you notice an injury, prepare a box with an absorbant towel at the bottom, and gently contain the injured animal. Contact the hospital at (310) 458-9453 to get further instructions. If you find a young uninjured animal you believe might be orphaned, contact the hospital as soon as possible to get instructions on whether the animal should be contained and brought into our Orphan Care Unit. It is very common for many species of birds to spend anywhere from 3-7 days on the ground learning how to fly. This is called the fledgling stage. Many people mistake these fledgling birds for orphans, but in reality the parent is still caring for them while they are on the ground. Unfortunately a lot of young animal are orphaned from tree trimming incidents. The best way you can help young animals is to wait until December to trim your trees!

When Birds Collide with Windows

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By Denys Hemen, Hospital Manager

Western Scrub Jays are often victims of window strikes
Photo by Alyssa Schlange

It’s a sight–and sound– sure to startle anyone who is a witness; you look up to see a bird hit your window, and immediately run outside to check on the welfare of the unfortunate creature. An estimated billion birds die from window stricks annually in the U.S. alone. Along with attacks by outdoor cats, window strikes are among the leading causes of the steep population decline seen in almost every species of songbird.

Birds collide with windows because they do not see them as solid structures and try to fly through them. Even small windows can be a problem because birds often look for narrow escape routes when being chased by predators. A bird may also fly into glass because a building’s surrounding vegetation is reflected onto the surface of the windows, or there is vegetation inside that the bird can see and attempts to fly into it. Glass walls installed around properties and on balconies are especially troublesome for birds.

California Wildlife Center receives dozens of birds each year with eye, head, and shoulder trauma from window collisions. Although the cause for much of this trauma is unknown, there were 65 patients last year brought to CWC because a rescuer had seen or heard the window strike. Not all birds are fortunate enough to recover from window strikes. Most are taken by predators while in a stunned state, and others may stumble off and perish while hidden from view.

If you have windows that birds are drawn to, there are a few options to prevent collisions. By far the easiest remedy available is bird tape. This reflective tape gives the window an appearance that resembles a solid structure. Other options available are “bird-proof” glass and adhesive films that can be applied to give the window the appearance of impermeability. Please remember always to keep bird feeders away from your windows.

If you witness a bird striking a window, there are a few things you can do to help. Quickly find a box suitable for the bird’s size that can be closed. Place something soft in the bottom, such as an old t-shirt or a towel, and puncture the box several times to provide adequate ventilation. Gently pick up the bird using your hands and quickly place the bird in the box, closing it immediately. If it is a larger bird, you may cover it with a towel when you pick it up to aid in its capture and to protect you from a bite. For birds of prey, such as hawks or owls, never attempt to pick them up with bare hands. Turn your box sideways and try to push the bird into the box using a broom or similar tool. For larger birds or birds of prey, keep the bird somewhere dark and quiet and call CWC at (310) 458-WILD. If it is a small songbird that struck your window, you can bring the bird inside to a quiet room for two hours. After that time, go outside and open the box. Sometimes the bird is only stunned and needs a little time to recuperate in a safe place. In this case, the lucky bird will fly out of the box and your work is done! If the bird is unable to fly or stand after this time, please contact CWC immediately.

 

Owl Rescued from Soccer Net

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by Jennifer Brent, Executive Director

Owl in soccer net, Photo by Fernando Romero

The day after Christmas we received an urgent call from the folks over at Chaminade College Prep in West Hills. They had found a Great Horned Owl caught in their soccer net. Students started to cut him free but were concerned about handling the owl. We were able to send Heather Henderson from the Marine Mammal rescue team to try to rescue the trapped bird. Throughout the rescue, the owl was calm and relaxed, but once she was completely separated from the netting, she regained her normally wild demeanor.

Heather transferred her to our hospital for our vet to check for injuries.  The owl had suffered abrasions to a few toes on her left foot and perhaps a minor injury to her wing.  X-rays revealed no actual signs of breakage, and she was confined to cage rest for a few days because of the duration and extent of her entanglement in the netting.

Owl being examined by CWC staff, Photo by Jennifer Brent

We did a test flight with the owl in one of our fully enclosed outdoor flight pens, and she soared! Volunteer Corby Sandberg, who brought the Great Horned Owl back to West Hills for release, said, “It was an uplifting experience…carrying the box with the owl in it felt light as a feather. When I opened the box and tipped it on its side – after some long pauses and curious wide-eyed looks around, it didn’t walk out, it swooped out without even a running start!”

Thanks again to the alert and caring students at Chaminade and to our volunteers who are able to assist with returning these wild creatures back where they belong.