LSM1303 Animal Behaviour

Links of to crabs/articles mentioned:

• Fiddler crabs in the mangroves of Singapore – link
• About Fiddler crabs – WildSingapore.com – link
• Orange fiddler crab, Uca vocans – link
• Face-banded sesarmine, Perisesarma eumolpe – link

See also this lecture on “Perspectives on Ocean Science: Listening to Whales” UCTelevision – link.

“Scientists Discover Singing Mice,” by Walter Butler. Buzzle.com, 05 Nov 2005 – link.
Researchers at Washington University were pleasantly surprised to discover that male lab mice sing a happy tune whenever they pick up the scent of a female mouse—it’s just too high for our ears to hear it.

“For decades, scientists have been aware of the high-frequency sounds that male mice produce whenever they pick up the scent of a female mouse. The babbling sounds are undetectable by human ears, but to a female mouse the noises probably sound like the crooning of Mouse Torme. Scientists have always assumed the chatterings had something to do with courtship, but they have not been certain.

They are now certain, however, that the sounds aren’t so much babbling nonsense but more complex and interesting than previously thought. “It soon became … apparent that these vocalizations were not random twitterings but songs,” said researcher Timothy Holy. “There was a pattern to them. They sounded a lot like bird songs.” The high-frequency sounds, undetectable by human ears, were recorded by Washington University School of Medicine researchers and amplified for human ears.”

Male mice serenade potential partners with ultrasonic song (PLOS)

Original article: Holy T. E. & Z. Guo, 2005. Ultrasonic songs of male mice. PLoS Biol, 3(12): e386. doi:10.1371/journal.pbio.0030386 – link

Yes, you will see cuteness personified in this highly vocal relative of the rabbit, the pika (Ochotona sp.). And David is pretty charming too…

Domestic cat vocalisation: Chirping and chattering:

A highly amusing collection of cat vocalisations which sound like words! Domestic cats may vocalise more to owners than to each other due the reinforcement they receive from them.

There are many more clips on youtube each year and you will realise some breeds are more vocal than others.

“Subtle chemical signals, or pheromones, have long been known to draw pairs together within the same species. In mice, for example, experiments showed that pheromones acted as attractants between males and females who were genetically similar except for a difference in a certain type of immune system gene – the HC (major histocompatibility locus). This pairing gives their offspring an advantage in beating back disease organisms.”

So the question is, can humans smell out partners with complementary genes?

See Teacher’s Domain for the background essay.

I know some of you missed this so here is the National Geographic Wild Chronicle video, from YouTube:

Some articles about bees and wasps in Singapore:

• “What are Hymenopterans? The world of bees and wasps,” by Marcus Ng. Celebrating Singapore’s Biodiversity, 03 Feb 2010 – link.
• “Beesy in Singapore,” by Marcus Ng. Celebrating Singapore’s Biodiversity, 03 Feb 2010 – link.
• “Hooked on Hymenopterans,” by John Lee. Celebrating Singapore’s Biodiversity, 03 Feb 2010.
  • Part 1 – link
  • Part 2 – link

The incident I referred to:

“50 students and a teacher attacked by bees in Labrador Park,” by Wong Mun Wai. Channel NewsAsia, 05 Jan 2007

SINGAPORE: A group of students and a teacher were attacked at Labrador Park by a swarm of bees on Friday. The Singapore Civil Defence Force said they were stung on their necks, arms and legs at about 12.30pm.

The Personnel Decontamination Vehicle was deployed immediately. Paramedics set up a triage to assess the injuries, and 51 casualties – 50 students and one teacher – were sent to two hospitals. – CNA/so

Related articles

• “Bee attack: Don’t fight back, just run,” The Straits Times, 07 Jan 2007.
• “Snapping shots on mobile phone instead of rendering help first,” letter from Cho Yan Fatt. The Straits Times Forum, 10 Jan 2007.
• “Some people ignorant of wildlife around them,” letter from Anthony Lee Mui Yu. The Straits Times Forum, 12 Jan 2007.

See WildSingapore news for the reports in full.

Paul Ehrlich, David Dobkin & Darryl Wheye, 1988. “Cooperative Breeding” in The Birder’s Handbook: A Field Guide to the Natural History of North American Birds Including All Species That Regularly Breed North of Mexico. Simon and Schuster, New York.

Photo by Flickr user Jim Earle

They discuss the larger context of several species beginning with the Florida scrub jay which was highlighted in the lecture; excerpt:

“Scrub jays in Florida represent a group of populations that probably were once in contact with the widespread western populations but are now totally isolated. Only in Florida are Scrub jays cooperative breeders, and there they reside in permanent, group-defended territories.

Although pairing and breeding can occur after one year spent as a helper, birds often spend several years as nonbreeding auxiliaries. Males may remain in this subsidiary role for up to six years; females generally disperse and pair after one or two years of helping. Helpers participate in all nonsexual activities except nest construction, egg laying, and incubation. Pairs with helpers are more successful — they fledge one and a half times more young than pairs without helpers.

All available habitat [oak scrub] is occupied, and populations appear to be stable from year to year, which means young birds are unlikely to find vacant space to set up territories of their own. In contrast, Western Scrub-Jays generally are not space-limited, and the probability of a young bird leaving home and finding a territory in which to breed is high.”

The essay is hosted on “Birds of Stanford” webpage. They provide an excellent summary of cooperative breeding including aspects from: Glen E. Woolfenden, John W. Fitzpatrick, 1984. The Florida Scrub Jay: Demography of a Cooperative-Breeding Bird. Princeton University Press, N. J., USA. 406pp. Look under “Essays” and click the link for “Alphabetical order” to find “Cooperative Breeding”.

Click to see the BBC Video with a breathless David Attenborough getting quite close to a Beachmaster!

“More than 50 oriental pied hornbills now roam Pulau Ubin, Changi and other parts of mainland Singapore, up from about 20 in 2004.” – the following news article talks about the artificial nest project for the hornbills on Pulau Ubin – “‘Intelligent nests’ for pied hornbills in Singapore,” by Grace Chua, The Straits Times, 08 Jan 2009 – link.

Bird Ecology Study Group

See these links:

• “Artificial nesting cavities for hornbills,” by Wee Yeow Chin with Angie Ng and Pilai Poonswad. Bird Ecology Study Group, 20 Dec 2008.
• “Oriental Pied Hornbills partying at Pulau Ubin,” by Angie Ng & R Subaraj. Bird Ecology Study Group, 07 Feb 2008.
• “Oriental Pied Hornbill – breeding,” by Wee Yeow Chin with Jonathan Cheah. Bird Ecology Study Group, 05 Feb 2007

Bednarz, J. C., 1988. Cooperative Hunting Harris’ Hawks (Parabuteo unicinctus). Science, 239(4847): 1525 – 1527.

Abstract – Coordinated hunting by several individuals directed toward the capture and sharing of one Large prey animal has been documented convincingly only for a few mammalian carnivores. In New Mexico, Harris’ hawks formed hunting parties of two to six individuals in the nonbreeding season. This behavior improved capture success and the average energy available per individual enabled hawks to dispatch prey larger than themselves. These patterns suggest that cooperation is important to understanding the evolution of complex social behavior in higher vertebrates and, specifically, that benefits derived from team hunting a key factor in the social living of Harris’ hawks.

“Hawks stoop with a group to increase hunting success – cooperative hunting techniques,” by Christopher Vaughan. Science News, 02 April 1988.

Tag team competition extends beyond the professional wrestling arena. Groups of Harris’ hawks in New Mexico use a variety of cooperative hunting techniques, including a “relay attack,” to capture rabbits and hares.

Cooperative hunting, in which many animals team up to capture and share one large prey, has long been observed in a small collection of mammalian species including lions, hyenas and wolves. But this is the first documented observation of such coordinated hunting behavior in birds, reports James Bednarz in the March 25 issue of SCIENCE. “There have been reports of pairs of falcons hunting together during mating season, but the pairs weren’t very cooperative or successful,” says Bednarz, who did the work while at the University of New Mexico in Albuquerque and is now a staff member of the Hawk Mountain Sanctuary Association in Kempton, Pa.

Harris’ hawks are large hawks that normally survive by eating quail and other small birds. The hawks eat much better if they can capture rabbits or hares, but it is very difficult for a single hawk to do so because the speedy rabbits outweigh the hawks by as much as 3 to 1. Bednarz found that groups of four to six hawks increased their chances of capturing rabbits by employing group hunting techniques to seek out, then tire and confuse their prey.

… Read the rest of this entry »

Joubert, D., 2006. Hunting behaviour of lions (Panthera leo) on elephants (Loxodonta africana) in the Chobe National Park, Botswana. African Journal of Ecology, 44(2): 279–281.

Introduction – Megaherbivores like elephants and rhinos have been regarded as invulnerable to predation as adults (Owen-Smith, 1988; G. B. Schaller pers. comm.), although Guthrie (1990) suggests that lions hunted such large prey during the Pleistocene. Recently, there have been a number of observations of elephants killed by lions in northern Botswana, going as far back as 1985 (M. Slogrove pers. comm.). The hunting behaviour of lions on elephants, and the age and sex structure of the elephants killed, were observed at a waterhole in the Savute region of Chobe National Park. The first observed elephant kill was recorded in August 1991. Systematic records of elephants killed were made between 1993 and 1996.

Loveridge, A. J., J. E. Hunt, F. Murindagomo & D. W. Macdonald, 2006. Influence of drought on predation of elephant (Loxodonta africana) calves by lions (Panthera leo) in an African wooded savannah. Journal of Zoology, 270(3): 523-530.

Abstract – Data were collected on species killed by lions Panthera leo in Hwange National Park, Zimbabwe between 1998 and 2004. Lions killed predominantly large to medium-sized herbivores, concentrating on buffalo Syncerus caffer, elephant Loxodonta africana, giraffe Giraffa camelopardalis, wildebeest Connochaetes taurinus and zebra Equus burchelli. These species made up 83% of all lion kills found and 94% of the biomass of kills actually observed.

Elephant calves made up an unusually large proportion of lion prey during the study period (23% of kills recorded). All elephants killed were dependent juveniles. Elephant calves appear more vulnerable during the dry months of the year, particularly in years of below average rainfall. Elephant calves are usually well protected. However, high-density aggregations of elephants around limited water sources during the dry season may deplete local food resources, forcing elephant herds to travel large distances between water and forage. Under these circumstances, elephant calves may become lost or separated from family groups, accounting for their high incidence in lion diet.

See also “The killing fields,” by Damian Whitworth. The Times (UK), 04 Oct 2006.

Emlen, S. T. & P. H. Wrege, 2004. Size dimorphism, intrasexual competition and sexual selection in Wattled Jacana (Jacana jacana) a sex-role reversed shorebird in Panama. The Auk, Apr 2004.

Photo source: Wikipedia

Abstract – We studied sexual size dimorphism, intrasexual competition, and sexual selection in an individually marked population of Wattled Jacanas (Jacana jacana) in the Republic of Panama.

Males are the sole incubators of eggs (28-day incubation) and primary providers of chick care (50-60 days). Females were 48% heavier than, and behaviorally dominant over, males. Females also showed greater development of secondary sexual characters (fleshy facial ornamentation and wing spurs) than males.

Both sexes defended territories throughout the year against same-sex conspecifics. Competition for territorial space was intense, and many individuals of both sexes did not become breeders. Resident females further competed with one another to accumulate multiple mates, resulting in a mating system of simultaneous polyandry.

Female and male residents (territory holders) were larger, heavier, and more ornamented than adult floaters of the same sex. Larger and heavier females also had more mates than smaller females. Body size was thus a critical predictor of success in intrasexual competition for territories (both sexes) and for mates (females).

…click to read more.

See also:

• “A male’s work is never done,” by Les Line. International Wildlife, Jul-Aug, 2000.
• “Jacanas and Polyandry,” (video and background). PBS: Evolution Library.