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alala breeding season

4

`Alala Population Soars Past 100

Hatching can be an exhausting process! This brand-new 'alala rests after a successful hatch.

May 13 was an exciting day: our first `alala of the 2012 season hatched at the Keauhou Bird Conservation Center! Just like all our previous `alala breeding seasons, this first chick was eagerly awaited and anxiously nurtured through its first few days (see video below). Over the past three weeks, another seven `alala chicks have hatched. Crucially, on May 31, we celebrated reaching the major milestone of 100 ‘alala in the entire world population! This is quite an achievement for a population that was down to a low of 20 individuals in 1994 and is currently considered extinct in the wild. In fact, following subsequent hatches, the population currently stands at 102 birds. We are hoping for several more chicks in the weeks to come.

This is one of Po Mahina's torpedo-shaped eggs.

This year, we have continued to apply the strategy of “assisted hatching” for several of our eggs. For example, our first two chicks are siblings from the same clutch of eggs, and both required assistance to hatch successfully. Their mother, #152 Po Mahina, is only 3 years old, and this was her very first clutch. Already it seems that Po Mahina has a tendency to lay long, narrow eggs, almost torpedo-shaped. This had implications for these two chicks; in the very final stages of the incubation period, each should have been ready to chisel the cap off its eggshell with the egg tooth on the beak. However, in both cases, the chick’s head and neck was wedged so tightly into the narrow egg that they were unable to rotate inside to cut through the shell. Consequently, these chicks were in serious danger of dying from exhaustion or asphyxiation before even having the chance to hatch. In both cases, we performed the avian equivalent of a Caesarian section. With great deliberation, we carefully peeled back the eggshell piece by piece, pausing to investigate for landmarks in the hatching process (such as the retraction of blood vessels and yolk sac) before finally releasing the head and gently extracting the chick from the remnants of its shell.

Helping an 'alala chick hatch takes steady hands!

Obviously, assisting the hatch of a chick from its shell is considered a last resort, a result of the breakdown in the chick’s normal, natural hatching processes. It is quite probable that the high incidence of assisted hatching cases is a consequence of inbreeding depression, caused by the shallow gene pool of the `alala flock. It is tremendously satisfying to watch other hatchlings burst out of their shell under their own steam!

Those first two chicks are now nearly a month old and barely recognizable from the pink, naked, and helpless neonates that were extracted from their shells. With a covering of pin feathers and equipped with a raucous voice to rowdily beg for food, they are making great progress. Eventually, these two will become members of our captive-breeding flock. However, with the `alala population now exceeding 100 birds, our Hawaii Endangered Bird Conservation Program continues to be in a strong position to make plans with our partners for releasing and reestablishing `alala back in the wild.

Richard Switzer is an associate director of applied animal ecology at the San Diego Zoo Institute for Conservation Research. Read his previous post, Maui Bird Conservation Center Open House.

8

`Alala Season Begins With Flurry

The first 'alala chicks of the season are hungry!

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.

9

‘Alala: We’re Getting Closer

'Alala Kinohi

“I know, I know, I know, I know –oh-oh–oh,” says the crow through the door.

“What do you know?” I ask.

“Why-oh-why-wah-hah-hah” is the reply.

Obviously, this is not ordinary crow speech, but this is no ordinary crow. This is Kinohi, an ‘alala (Hawaiian crow) hatched in captivity 20 years ago. Growing up, he lacked other crows to socialize with, and so he developed an unusual vocabulary. But while we may find his human-like babble amusing, there is nothing funny about the fact that he will not breed.

With only 70 known ‘alala left on the planet (see post ‘Alala Season: Encouraging Start), Kinohi’s genes are extremely important. Last spring, it was decided that intervention was necessary. Kinohi was shipped from the Zoo’s breeding facility in Hawaii to the Wild Animal Park, and for nearly an entire year now, Dr. Barbara Durrant and I have been visiting him almost every day to train him for semen collection (see post Training an ‘Alala for an Important Job).

We like to think Kinohi looks forward to our visits. When we enter the anteroom to his new indoor-outdoor enclosure, he calls out, letting us know he knows we are there. As we cut up his mouse into a cup (the pieces are his reward for cooperating with us), Kinohi waits at the door, peering at our feet through the small space at the bottom. To position his eye low enough to see us, he hangs his head upside down, the top of his head resting on the floor.

Spring marks the beginning of the breeding season, and while the ‘alala in Hawaii have been building nests, Kinohi also has been responding to the lengthening daylight. A few weeks ago, he began saving part of his food reward in his beak. It is now his routine to pick up the pieces of mouse one by one, but after swallowing a few, he holds the rest in the back of his mouth. Then, when he has emptied the cup, he takes the morsels to the box that serves as his nest. We think he is trying to bring food to an imaginary mate. He mumbles in a whiny tone, moving the food pieces up and down over his tongue, giving his voice a gurgling quality. Eventually he leaves the nest box, lines up the pieces of mouse on a perch, and eats them one by one as though savoring each bite.

Bird sperm is quite different from the typical sperm of mammals; instead of a round head, the head of bird sperm is long and oval, and in some birds it has a corkscrew shape.

But something more exciting is now underway. Kinohi has begun producing sperm again. Although we have not been able to collect a sample directly from his cloaca, we did find sperm another way. This may sound strange, but after each training session, we wait for him to poop. Because feces, urine, and reproductive fluids all pass through the cloacal opening, it is possible to find sperm in a bird’s droppings. As soon as Kinohi defecates, we use a pipet to suck up the clear portion and take it back to the lab. In the past week, we have finally started to see sperm under the microscope.

The first day there were only a few of these cells, but a few days later, we found dozens in just a tiny drop. Only one of these sperm was motile, however; the rest were not even twitching, but that is not surprising or discouraging, because the sperm were in the inhospitable environment of feces and urine. Over time, the number of sperm should keep increasing. With a little more persistence, perhaps Kinohi will give us a pure sample that we can send to Hawaii, and perhaps he will sire offspring at last (via artificial insemination).

Dianne Van Dien is a research technician for the San Diego Zoo’s Institute for Conservation Research.