It has been an amazing start to the 2011 `alala breeding season: we have already hatched eight healthy chicks at the Keauhou Bird Conservation Center in Hawaii! This brings the entire `alala population to 84 birds, and we anticipate many more eggs to go into incubators soon. One of these chicks represents a significant achievement in itself: the 125th `alala to hatch since the inception of the Hawaii Endangered Bird Conservation Program in 1993. Also exciting is the fact that these chicks are offspring from three different females. Notably, one of these chicks represents the first great-grand-offspring of the `alala that hatched from the very last egg harvested from the wild in 1996 (known to his friends as Oli), which has resulted in the valuable genetic line descended from the wild Ko`ohena pair.
Hatching begins with the embryo pushing its beak into the air-cell at the blunt end of the egg. From that point we continue to monitor the embryo even more closely, in case it needs assistance through the hatching process. (For more details of the `alala hatching process, including video, see Hatching Additions to the `Alala Flock.) So far, three of the chicks required a certain degree of meticulous and painstaking assistance, since there was a chance that they may not have made it on their own.
Once a chick has hatched, we essentially switch off the lights and leave it for a few hours to regain its strength. However, we do remove its eggshell, which we keep for subsequent chromosomal analysis of the blood remnants in the membranes to ascertain the chick’s gender.
During the hatching process, the embryo retracts its yolk-sac through its umbilicus into its abdomen, resulting in a very round belly and yellow areas clearly visible through the skin of the abdominal wall. This yolk-sac provides a valuable source of nutrition in the early days of a chick’s life; it is essential that the chick metabolizes its yolk-sac to prevent this becoming stagnant and leading to a life-threatening infection. Consequently the chick’s first feeds are relatively small and feature, among other food items, bee larvae‑a great source of liquid to keep the chick well hydrated.
As the chick grows, we increase its food intake. Initially the diet also includes cricket guts and scrambled egg. As the chick develops, we start to incorporate papaya, whole cricket abdomens, pinky mice, and waxworms, which are some of the items they will eat as adults. Since `alala are a species which, as adults, regurgitate a cast (pellet) of indigestible food, we must be cautious to slowly introduce the chicks to food that is high in chitin, such as insect exoskeletons. Throughout the chick’s development, we calculate its daily food intake, as well as its consumption of calcium. We must be careful that the chick’s body mass does not exceed its skeletal development, particularly in the leg bones – the last thing we want is a chick with a broken leg or rickets.
So far, we have been lucky enough not to face any major problems in the rearing of these chicks. In the past, `alala have proven particularly challenging to rear in their first ten days of life, due to weakness, poor begging response, and a compromised immune system, possibly as a result of inbreeding depression. Only one chick has given us cause for concern when it went through a long period of failing to produce fecals. Like all good animal keepers, we closely monitor the quantity and quality of fecal production, since it provides a valuable insight into the health of the chick. After modifications to increase the proportion of moisture in the diet, enemas, and internal manipulation of the chick’s swollen back end, manual stimulation of the cloaca proved the key in encouraging the chick to pass the huge back-log of fecal material, and it has now returned to good health.
What these young `alala lack in the “cute and fluffy” factor (blind, mostly naked, with typically only a little down on their heads), they make up for in personality. At this age, they can seem to be a little moody, and even appear to “give some attitude” if they don’t want to be bothered. Equally, they can be highly vociferous when expecting to be fed. This means that working in our hand-rearing rooms presents a delightful experience. These are still early days for these chicks; we only begin to relax slightly when a chick is fledged and weaned. However, we are doing everything possible to ensure these chicks stay healthy, and equally crucially, we hope to have number of new additions to the flock soon. Keep your fingers crossed!
Lynne Neibaur is a senior research associate at the Keauhou Bird Conservation Center.
Richard Switzer is the conservation program manager for the San Diego Zoo’s Hawaii Endangered Bird Conservation Program.