Archive for August, 2012

What Happens When Birds Disappear?

Posted by admin on August 10, 2012  |   No Comments »

Accidental introduction of an alien species to Guam created a laboratory for understanding what happens when a species—in this case birds—disappear from an environment. H.S. Rogers, Ph.D., Huxley faculty fellow at Rice University, presented her discoveries at the Environmental Society of America annual meeting August 8 in Portland, OR. In the 1940’s, the brown tree snake, native to Northern Australia and New Guinea, hitchhiked aboard U.S. military planes supplying Guam airbases. By the 1980’s, the tree snakes had virtually eliminated the forest birds of Guam. However, nearby Marianas Islands, without the brown tree snake, still have forest birds. This contrast created a perfect laboratory for Rogers’ investigation of what happens when birds disappear. The effects are both cultural and ecological.

Cultural effects
The birds remain an important indigenous cultural resource in the Marianas, the Chamorro on Guam miss the birds for many reasons. An entire generation has grown up without tasting the traditional foods or seeing a native forest bird, the chichirika, (Rufus Fantail) that appears often in Chamorro stories. “The younger generation has given the name Chichirika to the non-native Eurasian Tree Sparrow,” says Rogers. In addition, Guam residents never hear forest birdsong.

Mariana Fruit Dove
Credit: Isaac Chellman

Ecological effects
Rogers’ study has also investigated the ecological role of forest birds as seed dispersers and as consumers of pests. Although the pest research is still underway, Rogers’ spider counts show population growth of 2 to 40 times the number in comparable locations on islands with birds. Her working hypothesis is that the spiders may be replacing birds as top predators. However, nothing has replaced birds as seed dispersers. Birds eating fruit seeds deposit them far away from the “mother tree.” In addition, birds’ digestive action makes seeds 2 to 4 times more likely to germinate. Loss of the birds has caused two tree species to have a lower number of  germinating seeds.

Cautionary tale for U.S. economy
Rogers’ study presents a cautionary tale. Asian Carp are eradicating native species in Midwestern waterways, pythons are changing the Everglades, and the same Styela clava (sea squirt) that has devastated the Australian and English shellfish industry is threatening U.S. East Coast shellfish beds. The tree snakes cannot be eradicated, so the forest birds will never return to Guam. The question is whether the U.S. can stop the spread of non-native species that threaten important economic icons.

Cat Adoption: Summer-time is Prime-time

Posted by admin on August 7, 2012  |   No Comments »

The Oregon Humane Society (OHS), like most shelters, faces a huge influx of young cats each spring and summer. “August is the height of kitten season,” according to shelter spokesperson David Lytle.  “Because of this, OHS, during August, offers two cats for a single adoption fee. The regular $55.00 adoption fee includes spaying, first round of vaccinations, an  identifying microchip, a collar and ID tag, a free first vet exam, and one free month of health insurance.

Tiva
Credit: Oregon Humane Society

Tiva, a four-year-old domestic shorthair is one of the adoptable cats at  OHS.  This svelte 8-pound kitty is a funny, playful eye-catcher. Although she loves to snuggle and cuddle, shelter behavioral specialists caution that Tiva needs a home with older children, as she does enjoy some quiet time.

Petfinder.com, a website that directs potential adoptive families to animals available from local shelters,  also provides information on  finding the right cat to adopt. Petfinder’s advice is to consider an older cat. While kittens are adorable, their care requires an extraordinary amount of time. In addition, older cats have well-formed personalities and have reached their adult size, giving you a look at your cat’s personality as he or she will likely be day-to-day. A young adult, like Tiva, is often a very good choice and has a long life ahead of her.

During August, your OHS adoption fee also includes a second cat at no additional cost. OHS  always encourages people to adopt two cats. “Felines crave attention and stimulation, so when left alone they can be naughty,” says Lytle. “If you adopt a pair of cats that are compatible, they’ll keep each other entertained and out of trouble.” Petfinder’s library of articles emphasizes the importance of having space to adopt two cats and ensuring that the two felines are compatible. Reviewing these articles, you’ll learn more about cats, whether you’re a beginner or a veteran.

Adopting the right cat for you.

 

If you feel you need to justify your adoption, consider this: Pet companionship is a powerful force for comfort and stability in a world that seems a bit upside down.  Studies show that the simple act of petting your devoted companion lowers your blood pressure and stress hormones.

The Mayo Clinic on pets and health.

 

Friends Help Friends Faster: Not Just a Human Trait

Posted by admin on August 1, 2012  |   No Comments »

Credit: Giyarto / German Primate Center

Friends react faster when a friend calls for help than when a stranger calls, according to study results released July 31. Makes sense, except that the subjects in the study weren’t human.  They were crested black macaques (Macaca nigra). Dr. Antje Engelhard, working from an Indonesian field station near Mt. Tangkoko, tested the reaction of group members to alarm calls that macaques make when they see a python. (Pythons are one type of snake that eats macaques.) The alarm call of a macaque attracts other macaques to help drive away the predator. Analysis of video-recordings made by the researchers showed that friend macaques react faster than stranger macaques. Englehard concludes that social bonds are more important than kinship in cooperative defense against predators.

Credit: Google Maps and Shannon McKown

Macaques discover and mob a python. Watch carefully for the python!
This is a natural situation, caught on camera.
Here researchers play a pre-recorded alarm call
from a friend of the macaque in the video.
Here researchers play a recorded alarm call from a macaque
that is not friendly with the macaque in the video.
Note to all macaques: I am your friend! Seriously, getting a sense of scale in the videos is tough. FYI, those bad girls are 11+ lbs. with big ole’ canine teeth.

Here’s what you need to know: Male crested macaques weigh about 22 lbs., about twice as much as the average female, according to the Primate Information Center at the University of Wisconsin, Madison. In Tangkoko, on the island of Sulawesi, these primates travel in groups “varying from 27 to 97 individuals.” These macaques mainly eat fruit, but they also consume seeds and leaves, flowers, and pith (center portion) of many stems, as well as fungi, bird eggs, birds, lizards, and frogs.

Note to self: Always serve what the macaques like when throwing a dinner party for them.

 

Sources:

  • German Primate Center (2012, July 31). Friends help more promptly, at least in monkeys. ScienceDaily. Retrieved August 1, 2012.
  • Cawthon Lang KA. 2006 February 2. Primate Factsheets: Crested black macaque (Macaca nigra) Taxonomy, Morphology, & Ecology<http://pin.primate.wisc.edu/factsheets/entry/crested_black_macaque>. Accessed 2012 August 1.