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9 Exotic Mating Rituals of the Animal Kingdom

With Valentine’s Day around the corner, now is a good time to learn about the birds and the bees. Although the wild kingdom doesn’t have the same romantic love approach to reproduction that humans claim, animals follow countless mating rituals that we might not even be aware of. Let’s look at a few.

Peacock| 9 Exotic Mating Rituals of the Animal Kingdom

photo: Angie Bell

With their fancy feathers, it’s no surprise that birds take home the prize for most exotic courting routines. It was the peacock’s train that apparently inspired Darwin’s theory of sexual selection and the evolution of esthetic beauty. Male peacocks embody one of the most impressive courting displays of the avian world, and females are rather picky about their mates. In fact, the peacock’s female-attraction power is directly related to the perfection of a male’s spectacular train, including its overall length, the number of iridescent “eyes” that are present, and even the symmetry of their pattern.

Bowerbird | 9 Exotic Mating Rituals of the Animal Kingdom

Male bowerbirds are avian artists and spend anywhere from one week to a few months building the perfect little retreat for prospective females. These creative engineers decorate their bachelor pads with available resources, like seeds, berries, leaves, and other discarded items they can find. Many have a preferred color scheme and look for items to accommodate. Some species even use their beak or a piece of bark to paint their pad with an extra splash of color to attract a mate!

Hummingbird | 9 Exotic Mating Rituals of the Animal Kingdom

Shiny feathers on a male hummingbird are thought to indicate good health, so these birds use their brilliant plumage to their advantage. Some species will form a lek, consisting of up to 100 males looking for a match. If a female shows interests in one of the tiny suitors, he then performs a flying dance to win her over.

Impala | 9 Exotic Mating Rituals of the Animal Kingdom

A variety of horned mammals also exhibit unique performances during courtship. Male impalas, for instance, have a strange way of attracting females or warning off other males: they repeatedly stick their tongue out in a display known as tongue flashing.

Goat and sheep | 9 Exotic Mating Rituals of the Animal Kingdom

Size matters when it comes to the horns on a male goat or sheep. Head-butting clashes become more violent during breeding season, and the winner typically breeds with all the females in a flock or herd. So while fighting over females is frowned upon in human relationships, it’s go big or go home with the bachelor group for these hoofed mammals.

Hippo | 9 Exotic Mating Rituals of the Animal Kingdom

The dominant male in hippo society has the right to mate with all of his herd’s females, but gaining supremacy is a dirty job. Male hippos use their fan-shaped tails to fling their dung to attract a female and remind the herd of his territory.

Ring-tailed lemur| 9 Exotic Mating Rituals of the Animal Kingdom

While humans are concerned about smelling nice when attracting a potential mate, having a strong stench is a good thing for ring-tailed lemurs. During mating season, males compete for females through stink fights that involve smearing scent from glands onto their tail and jerking and swinging the tail to waft the sharp odor toward their opponent.

Elephant | 9 Exotic Mating Rituals of the Animal Kingdom

Chivalry isn’t dead in elephant society. Adult males usually don’t live with the main herd, but during breeding season, albeit short term, these emotive pachyderms spend anywhere from one hour to a few days courting a mate.

Bonobo | 9 Exotic Mating Rituals of the Animal Kingdom

In bonobo society, females take charge. Upon entering a new troop, females will breed with all the males and gain permanent membership only after giving birth. These highly intelligent primates have also been observed using sexual behaviors for social reasons other than reproduction, such as conflict resolution.

Do you have any animal mating rituals to add to our list? Share yours in the comments.

 

Jenn Beening is the social media planner for San Diego Zoo Global. Read her previous post, 14 Notable Safari Park Births of 2014.

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Nature’s Excellent Engineering Feat: The Egg

This kagu egg is just one example of nature's egg-cellent engineering feats.

This kagu egg is just one example of nature’s egg-cellent engineering feats.

Have you ever wondered why eggs are shaped the way they are? Or why egg shape varies with the species? Most eggs have one tapered and one wider end to ensure they roll only in a circular pattern. This ensures that the eggs do not roll out of the nest when they are turned by the parents. Some species lay eggs with a more pronounced small end, which make them roll in a tight circle. For example, seabirds like murres nest strictly on rocky cliffs and use no nest material at all. The elongated shape of their egg makes it less likely to roll off the cliff edge. Birds that make deep cup-shaped nests typically have rounder eggs, because there is less risk that the eggs will roll out of the nest when turned. Nature’s exquisite engineering continues inside the egg, too!

The egg itself is a self-contained home, supplying all the nutrients and safety for the growing chick inside. The duration of incubation varies, but all chicks will grow until there is so little space inside that it is difficult to move. When it is time to hatch, the chick has to get into the proper position, with the head under the right wing and the beak pointed upwards toward the larger end of the egg (being in the wrong position can be fatal). The large end of the egg has an air-filled space called the air cell. The chick must use its beak to pierce the air cell membrane so it can start breathing the air inside. As CO2 builds up in the air cell, it triggers the yolk sac to retract into the chick’s abdominal cavity, getting the bird ready for life outside the egg. The next step is to break out of the shell.

The beak has a hard, sharp, triangular shaped structure, called an egg tooth, on the top of the beak that assists in breaking through the eggshell. The chick uses its legs to rotate as it pecks through the shell until a hole is large enough to break out of completely. Once outside the shell, the chick can rely on its yolk sac for energy and nutrients until it is getting enough food from its parents, or is feeding on its own.

With such a complicated process there are bound to be occasional problems with completing the incubation and hatching process. But when these problems arise, we can learn from them and provide helpful feedback for our animal care staff, enabling them to make management adjustments that will maximize the reproductive success of the many amazing species of birds we have in our care.

April Gorrow is a Senior Pathology Technician at the San Diego Zoo Institute for Conservation Research.

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9 Animal Superstitions

Animal superstitions and creepy critters have been haunting cultures around the globe. We think it’s time to separate fact from fiction, the latter being partially responsible for some bad reputations surrounding some incredibly innocent creatures. It’s important to note that just because certain species are portrayed as terrifying monsters in the media or fancy folklore doesn’t mean that said animals are, in fact, flesh-eating freaks of nature. In other words, the expression “don’t believe everything you hear” exists for a reason.

So without further ado, keep reading for some animal-inspired myth busting.

Satanic leaf-tailed gecko

One look at the satanic leaf-tailed gecko and you’ll understand why this demonic reptile made the list. This master of disguise has a body that mimics a dead leaf, which protects the gecko in its native Madagascar. To trick predators, the satanic leaf-tailed gecko can also flatten its body like a pancake and deliberately shed its tail. Despite how scary this tiny reptile appears to be, it’s irrational to denounce the species for its kooky characteristics.

Aye-aye

The Safari Park’s Lemur Walk demonstrates how curiously cute these prosimians can be. Yet the Malagasy people of Madagascar believe that lemurs embody the souls of their ancestors. In fact, the word lemur stems from the Latin word lemures, which translates to “ghosts” or “nocturnal spirits.” In Roman mythology lemures weren’t just spirits—they represented lethal, vengeful spirits, the kind nightmares are made of. This misunderstanding has threatened the lives of one subspecies in particular, the aye-aye, which is often killed on sight because it’s perceived as a bad omen. The only bad omen here is the fact that lemurs status was recently moved from vulnerable to endangered on the International Union for Conservation of Nature’s (IUCN) Red List of Threatened Species this year.

Tasmanian devil

The Tasmanian devil got its moniker for its dark color and fierce temper. These nocturnal marsupials let out spine-chilling screams while feeding together at a carcass. When they feel threatened or excited, their little ears change to bright red. While their name appears to suit their style, what’s even scarier is the fact that Tasmanian devils are critically endangered. In other words, Loony Tunes’ exaggerated portrayal of Taz as a voracious lunatic may have done more harm than good. Currently, the San Diego Zoo is one of just two facilities in North America to house these little devils.

Snow leopard

As elusive as they are stunning, snow leopards have been creatures of Nepalese myths and Buddhist culture for centuries. Luckily for them, their reputations tend to be more positive than the aforementioned animals. Their shy and mystifying ability to almost disappear in their native habitat has established snow leopards as shape-changing mountain spirits to the local people of Central Asia, who know them as “ghost cats.”

Jaguar

Another mysterious big cat that’s earned a prominent place in local legends is the jaguar. These cool cats are depicted in ruins throughout Central and South America, but instead of symbolizing a spooky species, jaguars represent beauty, strength, and unparalleled intelligence in the New World. In fact, some tales suggest that jaguars move between worlds because they’ve adapted to life in the trees as well as on the ground. Their ability to hunt during the day and night is equally impressive.

Vultures

Most vultures depicted in cartoons, comics, or films reinforce that one-dimensional image we all have: a symbol of impending doom or death. Even though the entertainment industry has deemed this winged species as wickedly horrid, once you get past their harsh appearance, you’ll learn that some cultures actually idolize vultures. Aside from ancient mythology and rituals, vultures are crucial to habitats, as they remove dead carcasses without spreading disease. So instead of fearing vultures, we should thank them for taking care of at least one dirty job.

Crow

Another bird that’s been doomed by ancient legends and modern Hollywood is the crow. Despite the fact that the comic book series and subsequent action movie was based on a brutal story of murder and vengeance, Edgar Allan Poe’s preceding works in the mid-1800s further expanded the crow’s negative connotations. Perhaps its slick, dark plumage is to be blamed for the crow’s lack of love, but in nearly every culture’s mythological past– from Ireland to Islam–this species was associated with war, death, murder, and other terrifying nouns that keep us awake at night.

Gila monster

With a name like Gila monster, it’s no surprise that this species has one of the worst reputations in the reptile world. Native to northern Mexico and our southwestern states, this lizard is feared by humans for a bevy of false reasons. For starters, some people think the Gila monster can spit deadly venom, sting with its tongue, and even kill people with its poisonous breath. While the Gila monster is, in fact, venomous, a bite from one of these scaly creatures rarely causes death…in humans. Nothing to fear here.

Komodo dragon

The Komodo dragon is another victim of bad publicity. While it wins the prize for largest-living lizard in the world, people have feared the dragon because it’s believed that its saliva contains a deadly bacteria. The jury is still out on this one, so stay tuned for another blog that addresses this topic.

Join the fun! Share your animal legends and superstitions in the comments below.

 

Jenn Beening is the social media specialist for San Diego Zoo Global. Read her previous post, 7 Animals You Didn’t Learn In School.

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7 Animal Facts You Didn’t Learn In School

You don’t have to be an animal expert to appreciate the natural world. In fact, simple short cuts like the fun facts listed below, can be very conducive to gaining a better understanding of the Animal Kingdom. Enjoy!

Monkeys have tails and apes don't.

1. Monkeys have tails and apes don’t.
Since we have more in common with our great ape cousins than we do with monkeys, a good way to remember this fact is to simply look at your rear end.

There’s no such thing as a poisonous snake.

2. There’s no such thing as a poisonous snake.
Contrary to pop culture and older versions of Encyclopedia Britannica, snakes are venomous, not poisonous. If they were poisonous, touching or licking a serpent would be the more appropriate fear than death by snakebite. And that’s even debatable, since statistics show that out of 7,000 to 8,000 snakebites per year in the U.S., only 5 or 6 are fatal. Call it semantics, but the truth is only 10 percent of the 3,000 species of snake are venomous, meaning they inject toxins into their prey (biting or stinging). The difference is skin deep.

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Food Time!

The great argus pheasants share their aviary with a variety of birds, each with its own dietary needs.

The great argus pheasants share their aviary with a variety of birds, each with its own dietary needs.

It should come as no surprise to hear that the most interesting, and dynamic, part of the day in any bird exhibit is usually feeding time. Even though our birds have constant access to a nutritious and balanced diet, a keeper entering the exhibit with new food pans means there are usually some choice goodies that any fish-eating stork, mealworm-devouring woodpecker, or grape-gnawing fruit-dove can’t wait to get a hold of. While the scope of a keeper’s entire morning feeding routine may be too overwhelming to cover in one short blog, we can take a look at how exciting feeding time is in one particular bird exhibit at the San Diego Zoo.

The Malay great argus exhibit (just next to the lower tiger viewing glass) is home to a number of colorful characters. At any given moment you may witness the stunning fairy bluebird Irena puella singing his tune while making fast, powerful darts from perch to perch, the mischievous blue-winged sivas Minla cyanouroptera flitting from leaf to leaf, the hooded pittas Pitta sordida hopping in and out of the ground cover on spring-loaded legs. And in the background you may hear the black-throated laughingthrushes Garrulax chinensis and Chinese hwameis Leucodioptron canorum calling back and forth to their mates.

As vibrant and lively as this exhibit is throughout most of the day, things really start to get exciting when the birds hear a keeper approach. Their first clue that it is feeding time is probably when they hear the lock being unlatched. By the time I enter the exhibit, the birds have taken their stations and are ready for their breakfast.

Blue-winged sivas are the smallest birds in the aviary and get fed first.

Blue-winged sivas are the smallest birds in the aviary and get fed first.

When I first enter the exhibit, I am frequently surrounded on three sides with expectant birds. The first to get fed are usually the smallest birds in the exhibit: the blue-winged sivas. These little guys are usually embedded in the nearest foliage, chirping away. They can be hard to find, but when they see me looking for them, they pop their heads out of the foliage and fly out to catch their tossed mealworm. When they both have their breakfast treat, they retire to an upper corner of the exhibit to enjoy their grubs together. Two down, fourteen to go!

The Malay great argus Argusianus argus are usually next. I toss a few peanuts deep into the exhibit. As the male sprints away to hunt down his peanuts, I drop a couple at my feet for the female and her chick to enjoy.

By this time, the male white-rumped shama Copsychus malabaricus is growing impatient, and he is perched about 3 feet in front of my chest, staring straight at me. I toss a few waxworms (moth larvae that look like large maggots—not as gross as it sounds!) into the crook of the tree behind him. The voracious male usually inhales all the insects within reach. Though if he has chicks he is feeding, the male stacks as many bugs into his tweezer-like bill as he can before flying off to care for his chicks.

If I have timed the feeding right, the argus mom and baby have just finished their peanuts and are moseying over to their morning sun bath when the pittas hop over to my feet and declare they want their food—now! A reclusive species notorious for their solitary habits, pittas can fight over their food if they think their mate unfairly stole their worm. By tossing one redworm to my left and one to my right, the pittas about-face and hop to opposite ends of the exhibit, where they can enjoy their treat all by themselves.

After the fairy bluebird catches his third bug in mid-air, and the female shama has darted out from her ground cover to snag a forgotten cricket, the excited mob of birds thins to a mere congenial gathering. This is when the patient laughingthrushes and humble hwameis emerge to land on nearby perches. I toss a few bugs into the leaf litter and let them hop down to kick up their own food. As I finish setting out the morning food pans, I usually leave the exhibit to the pleasant, rhythmic sound of the laughingthrushes and hwameis kicking leaves, tossing twigs, and digging in the dirt in their search for that last, elusive grub.

Mike Grue is a senior keeper at the San Diego Zoo. Read his previous post, His and Her Massages: Collared Lories.

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Win a Spot for Lorikeet Landing Tweet-up

Photo by Lisa Diaz

Photo by Lisa Diaz

*PARK ADMISSION REQUIRED FOR NONMEMBERS*

UPDATE 12/26/13: ALL TWEET-UP SPOTS ARE FULL. STAY TUNED FOR THE NEXT TWEET-UP!

The Safari Park’s Lorikeet Landing experience now has twice as many birds, resulting in twice as much fun! To celebrate, we’re giving our loyal Twitter followers exclusive access to the exhibit on Saturday, January 4, at 9:30 a.m. before the experience opens. Because of limited capacity, only 20 people will be allowed to join.

Want in on this awesome VIP experience? All you have to do is tweet these exact words starting Friday, December 20, 2013:

Hey @sdzsafaripark I want to go to the #lorikeetlanding tweet-up on January 4th!

The first users to tweet the exact words above (one tweet per user) will win spots for the tweet-up. *By tweeting the above, you confirm that you agree to the terms and conditions below.* Please only enter if you are available to attend the event on the morning of Saturday, January 4, 2014, at 9:30 a.m. The winners will receive a tweet or direct message from @sdzsafaipark with more information on how to claim the prize. Space is limited for this event, so get moving!

Guests are also encouraged to participate in our Lorikeet Landing Instagram Contest, which ends the day after the tweet-up. Simply tag your Instagram photos and videos with #LorikeetLanding for a chance to win a private Balloon Safari for ten.

Terms and Conditions

*PARK ADMISSION REQUIRED FOR NON-MEMBERS*

1. NO PURCHASE IS NECESSARY TO ENTER OR WIN. A purchase will not increase your chances of winning. Participation constitutes entrant’s full and unconditional agreement to and acceptance of these Official Rules. The San Diego Zoo Safari Park Lorikeet Landing Tweet-up Contest (“Contest”) will be held online from 12:00 a.m. Pacific Time (“PT”), December 20, 2013 (“Sweepstakes Start Date”), to 9:00 a.m. PT, January 4, 2014 (“Contest Period”). Contest is sponsored by the Zoological Society of San Diego DBA San Diego Zoo Global (the “Sponsor”) who is solely responsible for all aspects of this Contest.

2. ELIGIBILITY. The Contest is open to legal residents of the United States of America who are 18 years of age or older as of “Contest Start Date.” Sponsor’s employees and their immediate families are not eligible to participate or claim a prize. Void where prohibited or restricted by law. All federal, state and local laws, rules and regulations apply. By participating, entrants agree to abide by all terms of these Official Rules and to the decisions of the judge, and waive any right to claim ambiguity in the Contest or these Official Rules.

3. HOW TO ENTER. 1.) As of 12:00 a.m. PT, December 20, 2013, the entrant must:

a. Have a Twitter® account: If you are not a member, you may sign-up here: http://twitter.com

b. Tweet the specified text: Hey @sdzsafaripark I want to go to the #lorikeetlanding tweet-up on January 4th!

No mechanically reproduced entries will be accepted.

4. INTERNET LIMITATIONS OF LIABILITY. If for any reason this Contest is not capable of running as planned due to infection by computer virus, bugs, tampering, unauthorized intervention, fraud, technical failures, or any other causes beyond the control of the Sponsor which corrupt or affect the administration, security, fairness, integrity or proper conduct of this Contest, the Sponsor reserves the right at its sole discretion, to disqualify any individual who tampers with the entry process, and to cancel, terminate, modify or suspend the Contest in whole or in part, at any time, without notice and award the prizes using all non-suspect eligible entries received as of this termination date. The Sponsor assumes no responsibility for any error, omission, interruption, deletion, defect, delay in operation or transmission, communications line failure, theft or destruction or unauthorized access to, or alteration of, entries. The Sponsor is not responsible for any problems or technical malfunction of any telephone network or telephone lines, computer on-line systems, servers, or providers, computer equipment, software, failure of any e-mail or entry to be received by the Sponsor on account of technical problems, human error or traffic congestion on the Internet or at any Website, or any combination thereof, including any injury or damage to participant’s or any other person’s computer relating to or resulting from participation in this Contest or downloading any materials in this Contest. CAUTION: ANY ATTEMPT TO DELIBERATELY DAMAGE ANY WEBSITE OR UNDERMINE THE LEGITIMATE OPERATION OF THE CONTEST IS A VIOLATION OF CRIMINAL AND CIVIL LAWS AND SHOULD SUCH AN ATTEMPT BE MADE, THE SPONSOR RESERVES THE RIGHT TO SEEK DAMAGES OR OTHER REMEDIES FROM ANY SUCH PERSON (S) RESPONSIBLE FOR THE ATTEMPT TO THE FULLEST EXTENT PERMITTED BY LAW. In the event of a dispute as to the identity of a winner based on a Twitter account, the winning entry will be declared made by the authorized account holder of the Twitter account submitted at time of entry. “Authorized account holder” is defined as the natural person who is assigned to a Twitter account by Twitter Inc.

5. SELECTIONS AND NOTIFICATION OF WINNERS. Winners will be determined by chronological order of entries (first come first serve); the first users to enter earn priority spots. Winners will be notified by Twitter direct message or tweet  and need not be present to win. Only one winner per household. Winners will be required to execute and return an Affidavit of Eligibility/Release of Liability/Publicity Release and completed IRS W-9 form within 30 days of issuance. Winners are solely responsible for all travel costs that might be required to visit the San Diego Zoo. The winner will be disqualified and an alternate winner will be selected if a selected winner fails to comply with these rules, cannot be contacted, is ineligible, fails to claim a prize, or fails to return the completed and executed Affidavit and Releases in the stated time period as required, or if the prize notification or prize is returned as undeliverable. Acceptance of a prize constitutes permission to use the winners’ names, likenesses, and statements for promotional and publicity purposes without additional compensation or limitation unless prohibited by law. All decisions of the Sponsor regarding the selection of winners, notification and substitution of winners in accordance with these Official Rules shall be binding and final.

6. PRIZES AVAILABLE. Winners will receive a TBD amount of spots for the Lorikeet Landing tweet-up on January 4, 2014. The prize is not transferable, assignable, or redeemable for cash and if not used will be forfeited.

7. INDEMNIFICATION AND RELEASE. By entering the Contest and participating in any promotions relating thereto, each entrant agrees to release and hold Sponsor, its respective affiliates, subsidiaries, parent companies, officers, directors, shareholders, employees, agents, participating retailers, and any other companies participating in the design, administration, or fulfillment of this sweepstakes and their respective officers, directors, employees, and agents, harmless from any and all losses, rights, claims, injuries, damages, expenses, costs, or actions of any kind resulting in whole or in part, directly or indirectly, from participation in this sweepstakes or any sweepstakes-related activity, or acceptance, possession, use or misuse of the prize or parts thereof, including without limitation personal injuries, death, and property damage and claims based on publicity rights, defamation, or invasion of privacy.

8. TAX INFORMATION. All applicable Federal, state and local tax liabilities and any other incidental expenses, fees or costs associated with the receipt or use of any prize are the sole responsibility of the winner.

9. WINNERS LIST. For an Official Winners List (available after January 4, 2014, and through December 31, 2014) or a copy of these Official Rules (PLEASE SPECIFY WHICH), send a self-addressed, stamped envelope to: San Diego Zoo Global, P.O. Box 120551, San Diego, CA 92112-0551.

10. SPONSOR. San Diego Zoo Global: P.O. Box 120551 San Diego, CA 92112-0551

Matt Steele is the social media planner for San Diego Zoo Global.

 

 

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Guam Rails Fly Home

Guam rail

The Guam rail Gallirallus owstoni, a small, flightless bird, is extinct in the wild. This species was abundant as recently as the early 1960s, but due to the introduced brown tree snake, the rail is now virtually extinct in its historical range of Guam. As part of the AZA’s (Association of Zoos and Aquariums) Species Survival Plan (SSP), several institutions are diligently working to manage this species and work toward reestablishing it in the wild. As of last summer, there were 159 Guam rails in AZA institutions and in captivity on Guam. This number qualifies the Guam rail as a “Yellow” SSP, which means that the population is potentially sustainable but requires careful management to increase its sustainability.

As part of SSP recommendations, the San Diego Zoo’s Bird Department was involved this past March in sending five Guam rails to Guam. The birds we sent are candidates for release into the wild and are genetically diverse additions to the captive population housed on Guam. Our male, whom you may remember along the trail to the old Lory Loop, along with three others from the San Diego Zoo Safari Park and one from the San Antonio Zoo, were gathered here to undergo a pre-shipment quarantine period, as all exported birds are required to do. Our zoo and Disney’s Animal Kingdom have been designated as U.S. quarantine stations for Guam rails. All five birds were housed in mosquito-proof pens at the Zoo’s Jennings Center for Zoological Medicine for their quarantine period. Various health panels were performed by our veterinary staff to ensure the health of the birds prior to shipment.

Shipping procedures were carefully followed according to International Air Transport Association specifications. Crates for the Guam rail were carefully custom made by Dave Durflinger, a carpenter from our Construction and Maintenance Department. Each compartment had special care taken so that the birds would travel in comfort and safety: carpet on the floor, foam on the roof, and mosquito netting over every opening. The mosquito netting is required for birds traveling to any island country so as to prevent mosquitos from traveling along. Jaime Paramo, our resident crate expert, put the final touches on the crate. The Guam rails were traveling in high style!

While all of the pre-ship preparations and health exams were proceeding, the curatorial staff was working hard to take care of all the legal documentation for the shipment, making arrangements for the flights to Guam and arranging the required U.S. Fish and Game inspection of the birds in their crates. Carol Dittmer in the curator’s office even made arrangements with the Honolulu Zoo to check on the birds during their layover in Hawaii. As you can see, it is truly a group effort to get these birds to their destination!

The Guam rails arrived safely at their destination on March 15. I checked with the staff at the facility where the birds are housed: all are currently doing very well. The male that was on Lory Loop is a likely candidate for staying at the station and being part of the resident population. The three birds from the Safari Park are candidates for release into the wild. As the tree snake population on Guam has not been eradicated, the island is still not a safe release site for the species. Currently, the birds are released on the island of Rota, which is similar in habitat to Guam but has no tree snakes, so it is safe for the Guam rail. The bird from the San Antonio Zoo is still quite young, so his status has yet to be determined.

As you can see, sending these birds to Guam is a really big deal. It is a great example of how San Diego Zoo Global is a conservation organization, a demonstration of how our work helps endangered species, and an inspiration to our guests and staff alike to get involved and help endangered wildlife.

Amy Flanagan is an animal care supervisor at the San Diego Zoo.

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Parasites in a Pelican

American white pelicans fly in for a visit to the Safari Park.

We see the really weird stuff here in the Wildlife Disease Laboratories, and that’s why I love my job! As a pathologist, my role is to diagnose disease in our animals and, if possible, figure out its cause so that it can be treated or prevented. On animals that die, we perform a necropsy (the animal equivalent of a human autopsy) to determine the cause of death and monitor the health of the collection. Certain diseases can have serious implications for the individual animals or even for the species as a whole, since so many of the animals we work with are endangered.

But our collection animals are not the only ones we screen for disease. We also examine all wildlife that dies on our grounds, as these animals can act as sentinels for threats to native species as well as to our exotic animals or even to people. Sometimes, however, a disease entity turns up that is so new it presents more questions than answers. Such was a case I had not too long ago that started with a call from Megan Varney, one of our pathology technicians. “You’ve got to see this pelican’s liver!” she says.

The bird was a wild, young female American white pelican that was found dead at the San Diego Zoo Safari Park that morning. This native species with its characteristic pouch can often be seen visiting and enjoying the lakes at the Park. With their big, yellow bills, all-white plumage, and large wingspan (second only to the California condor among North American birds), they are hard to miss! I dash to the necropsy room to see what Megan has found in this one. For a pathologist, it is a truly spectacular sight. The liver, normally a solid brown, is swollen and riddled with yellow spots, not just on its surface but on the inside, too (see cross-section at left), and the spleen has a similar appearance.

Yikes! It looks like something has caused large numbers of cells in the liver and spleen to die, creating the yellow lesions. But what? I run through a list of possible causes in my head, but I have a feeling that this could be something new. To the microscope! Sure enough, looking at slides made from thin sections of liver tissue under the microscope, I can see infectious organisms in the lesions. They appear as pale-purple blobs mixed with the dead pink liver cells.

It is a single-celled organism, a protozoan parasite, but not one with which I am familiar. Thankfully, I am not alone—even our parasitology consultant is stumped! I send tissue to our Molecular Diagnostics Laboratory, which can isolate the DNA of this mystery organism by PCR and, we hope, get it identified. Samples of tissue are also sent out to be looked at with an even bigger microscope, an electron microscope. The results of these additional tests agree: the parasite is a flagellate called Tetratrichomonas. Although known to be a parasite of ducks and geese, it has rarely been seen to cause disease, and certainly not in a pelican.

So what does this mean for the other animals at the Safari Park? Thankfully, it appears not much. Several months have passed with no new cases, and this unlucky pelican might turn out to be the only case we ever see. Many questions remain unanswered, though: Why this bird? Where did she get the infection? And what else might be susceptible? We are continuing to investigate these questions and more by working to better characterize this organism. Perhaps we’ve discovered a new strain or species! In the meantime, I will also present this information at a national zoo and wildlife pathology workshop to make others aware. And now that we know what it is, we are on the lookout with heightened surveillance so that we can be prepared for whatever happens next. In this job, it really is something new every day!

Rachel Burns is the Steel Endowed Pathology Fellow, Wildlife Disease Laboratories, San Diego Zoo Institute for Conservation Research.

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Green Woodhoopoe: Quirky or Clever?

Last week I wrote about two green woodhoopoes that had a curious behavior of feeding other birds (see post Green Woodhoopoe: Nature’s Room Service) Well, I have another story for you; this one involves another male green woodhoopoe feeding another bird that did not want to be fed!

A few weeks ago, my coworker Mark was tossing bugs to a few of the insect eaters in Scripps Aviary at the San Diego Zoo. He had the usual line of characters waiting for a cricket to be tossed their way: the long-tailed hornbill was patiently perched, the white-crowned shrikes made their boisterous appearance, and the racket-tailed roller was sulking on her branch. All was going well when suddenly the woodhoopoe male landed in the crowd of gathered birds. He already had a cricket in his mouth, so Mark could only guess that he might have been looking for his mate to feed. Instead of finding his mate, though, the woodhoopoe inadvertently landed next to the racket-tailed roller. Surprised, the roller turned, opened her mouth, and prepared to roundly scold the woodhoopoe. Only she never got that far—she was interrupted. Before she could berate him, the woodhoopoe had deftly shoved the cricket into her gaping mouth, flown away, and (probably) congratulated himself on a job well done!

Okay, enough of the anecdotes, what’s really going on here? Are green woodhoopoes just oddly obsessed with feeding other animals? The evidence to me suggests “yes!” But there may be a reason nature has given woodhoopoes this quirky characteristic. Woodhoopoes are cooperative breeders; this means that a group of 4 to 8 woodhoopoes (sometimes up to 14 individuals) helps to raise the offspring of just the dominant male and female of the group. Who are these helpers? Frequently, the helpers are the offspring of the breeding male and female. In the wild, the tree-cavity nests woodhoopoes need can be hard to come by. With a lack of nests available, many woodhoopoes help to raise their siblings instead of starting their own family. The helpers may not have the genetic success of breeding, but they do help to increase the success of their genes if they improve the survival rate of their brothers and sisters. As time passes, the helpers may inherit a breeding position from their parents or they may strike out on their own and try to find a mate and a nest.

You can probably guess by now why woodhoopoes have a tendency to feed other birds: these helpers bring a constant supply of food to their siblings! Feeding birds that are neither their offspring nor their mate is not just a quirky characteristic of the green woodhoopoe but also a means of their survival. How cool!

Mike Grue is a senior keeper at the San Diego Zoo.

5

Sociable Weavers: Amazing Architects

One of the most intriguing species of bird that I have the pleasure of working with is also one of the most overlooked: the sociable weaver. Their exhibit is located in the San Diego Zoo’s Lost Forest, across from the gibbons. It’s easy to pass right by them, since at first glance their appearance is not that impressive. They look very similar to the common house sparrow, so what could be that interesting about them? Please allow me to enlighten you.

Athena checks the sociable weaver nest.

Despite their small size, they are capable of completing an extremely large task. They create the largest communal nest of any bird in the world! These nests are often referred to as “apartment complexes,” as they are used for both roosting and breeding. A single colony nest can weigh up to a ton and may house over a hundred birds. There are several chambers in the nest, and the colony may use it for many generations.

In the interest of being efficient, these birds are constantly communicating with each other and constantly building! You can hear all the chatter as you approach their exhibit. You’ll also notice a large pile of nesting material on the ground that they can pull from throughout the day. As their keeper, it is my job to keep the material coming, and it has been a challenge to provide the proper items.

In the wild they would have access to a variety of plants, and each item they add to the nest serves a different purpose. Sociable weavers prefer rigid material for the roof, chambers are made stable with various dried grasses, access to these chambers are usually surrounded by straw, and the chambers are lined with soft materials (grasses, feathers, cotton, etc.) for comfort. Over the years they have been offered feathers, silk floss, camel hair, small sticks, pine needles, Bermuda hay, and dried grasses. I have worked with this colony for 4½ years now, and I have learned that their favorite items are pine needles, Bermuda hay, and dried Pennisetum grasses. And they certainly keep me busy with the challenge of providing them with plenty of material every day!

Recently the nest was the largest that it has ever been. Due to its ever-increasing size, as well as the weather, portions of the nest have started to fall. This is a natural process, and the birds have already begun investigating other potential nesting locations. They may also choose to repair the areas where chunks of the nest have been lost. Whatever the outcome may be, the colony benefits as they have the opportunity to renew their nest and start with fresh material. A healthy nest helps to maintain a healthy colony of birds.

The next time you’re walking along Monkey Trail in Lost Forest, take a moment to watch these active birds. I’m sure you’ll be impressed by their nest-building skills. And since the San Diego Zoo is home to the only sociable weaver colony in the United States, you won’t want to miss the opportunity to see them up close!

Athena Wilson is a senior keeper at the San Diego Zoo. Read her previous post, Welcome to the World, Screamers!