Behaviour of Emu Birds
Cherryl Miranda*, Y Ravindra Reddy2 and Shwetha H S3
*Associate professor, Dept. of LPM, Veterinary College, Athani, KVAFSU, Karnataka
8074360721
2Associate Dean, CDT, SVVU, Tirupati
3Assistant Professor, Dept. of VPB, Veterinary College, Athani, KVAFSU
ABSTRACT
Emus are raised commercially across the world for their highly valuable meat, oil, skin, and feathers. The emu is the second largest living bird with average height of 5.7 feet (1.75 meters). Males weigh 110 to 121 pounds (50 to 55 kilograms), and females weigh about 11 pounds (5 kilograms) more than males. The timing of breeding in emu may be influenced by a range of environmental factors including food availability, rainfall, and social and behavioural cues, but seasonal changes in photoperiod is probably the major cause.
Key words : Emu , Behaviour , Vocalization, Courtship, Breeding, Pairing
Introduction :
Emu is a large flightless bird of ratite family, native of Australia, introduced into India for commercial exploitation for production of meat, leather and oil extracted from fat, having therapeutic and cosmetic value. Emus are docile unlike ostrich with body weight of 45 to 50 kg and 5 –6 feet in height having a lifespan of 30 years with a productive life of 15 years. Scanty literature is available on behaviour of emu birds. The present study focuses on the general behaviour and reproductive behaviour in particular in the farmed emus.
Material and Methods:
The observations on Emu birds stationed at livestock Research Station, Palamaner over a period of 5 years formed the basis of study. Hence the present article is an overview of the observations made on general and reproductive behavior of Emu birds housed at the farm premises.
Results and Discussion:
Based on the observations made Emu behaviour could be classified under two heads.
- General behaviour
- Behaviour during breeding season
General behaviour:
Emus are docile by nature and adapt to human presence, even if a stranger enters the pen without unduly alarmed. Try to peck at the new things (belts, Pen) when a person enters the shed. It will even respond to the sounds made by a person and walks with person. Emus are fast runners and they run in circles early in the morning. Fruits, seeds, plant growth, insects, other tiny creatures, and animal waste are all consumed by emus. They also pick up pebbles and small stones that aid in grinding of food in gizzard. Moreover, charcoal is something they frequently consume.
A peculiar thing is they try to enjoy rain unlike other animals. They tried to puddle in mud water and enjoy being hosed with water during summer. These birds peck at the injuries caused on other birds. Emus are aggressive in behaviour as the breeding season approaches and more vocalization is observed. They make booming, banging, and grunting noises as their cries. The males can be heard from a great distance when they make their calls, which can sound like “e-moo”. Females emit a distinctive resonant, booming sound (Patodkar et al. 2009).
Reproductive Behaviour in Emu
Emus are primarily monogamous, but occasionally polygamy in seen. This coincides with findings of Blanche et al (2000) and Taylor et al (2000), who reported that microsatellite studies have clearly shown that the nest contains eggs from more than one female. Emu reaches sexual maturity at two years of age and lays eggs during winter months of the year from September to February. The feed intake of the birds decreased during entire breeding season, which agrees with O Malley (1992), who states that annual cycle of reproductive activity in the emu is inversely related to annual cycle of appetite. The timing of breeding in emu may be influenced by a range of environmental factors including food availability, rainfall, and social and behavioural cues, but seasonal changes in photoperiod is probably the major cause (Sharp, 1996). At the onset of breeding season, behavioural changes can be classified as follows
1.Vocalization
2.Pairing of birds
3.Courtship
4.Breeding
5.Coupulation related activities
6.Egg related behaviour
Vocalization:
Male emu birds make a grunting/growling sound. Emu hens are dominant and vocalize by making a drumming sound during the breeding season. A lot of drumming, grunting occurs mostly after dusk and before dawn.
Pairing:
The birds that are seen together several times during daytime and sleep close to each other at night are best pairs to breed. Birds are aggressive and start chasing each other and sometimes result in injuries. Best pair of emu birds eats, walk and stay at a specified spot together.
Courtship:
The courtship includes strutting, displaying of neck feathers, pecking of feathers in both the sexes. Due to behavioural changes during breeding season male emus become friendly with the hen emu and starts pecking of neck feathers. The courtship in emus can be confirmed by loss of neck feathers.
Breeding:
Emu are shy breeders and mating is most common at dawn and peak sexual activity is seen after dark at night and early hours in the morning. The male emu will peck the back of the female’s neck to encourage her to sit down for breeding.
Copulation related activities:
The female moves and settles down for sometime in the corner of pen. The interested male pecks the neck, back and tail region. Then the male squats around the female.
The female raises her tail feathers in sitting position indicating readiness for copulation. The male emu mounts on the hen emu by catching the neck and mates in les than a minute while making grunting sounds. These findings are in agreement with Minnar and Minnar.1992.
Egg related behaviour:
Once the hen emu lays the eggs, the responsibility of incubating eggs lies with the cock emu (Davies, 1976). During incubation period, male emu may go several days without food and do not appear mating with female in wild conditions. (Malecki etal,1997). On many farms, emus are bred in pairs and eggs are collected and incubated artificially. In our present study, some emus tried to cover the eggs with sand and mud present in the pen after laying of eggs.
References:
Blanche,D.Barret,C.D., and Martin G.B. (2000).Social mating and sexual behaviour in captive emus Dromius novaehollandiae.Emu.100,161-168.
Blanche,D. Talbott R.T. Blackberry, M.A. Williams K.M. Martin, G.B. and Sharp, P.J. (2001) Photoperiodic control of the concentration of Luteinizing hormone, Prolactin in emu birds.
Davies, S.J.J.I.(19760.The natural history of the emu in comparision with that of other ratites. n ‘The 16th International ornithological congress’ Pp:109-120.
Malecki, I. A., Wiliams, K.M., Martin, G.B. and Sharp, P.J.(19970. Effect of season and incubation on reproduction in the male emu. In ‘Advances in comparative endocrinology- XIIIth International congress on comparative Endocrinology’ pp;431-437.
Patodkar, V. R., Rahane, S. D., Shejal, M. A., & Belhekar, D. R. (2009). Behavior of emu bird (Dromaius novaehollandiae). Veterinary World, 2(11), 439-440.
Sharp,P.J.,(1996). Strategies in avian breeding cycles, Animal.Reprod.Sci., 42,503-513.
Taylor,E.L.,Blanche,D.,Groth,D.,Wetherall,J.D. and Martin,G.B. (2000). Genetic evidence for mixed parentage in nests of the emu. Behavioural Ecology and Sociobiology 47,359-964.