HADADA IBIS ATHE T OREGON ZOO

By Charlie Rutkowski and Gwendolyn Gerdsen with a wire mesh (1x1 inches for the side netting and 2x2 for the top) to enclose it. The substrate has ranged from pea gravel to dirt n 1989, the Oregon Zoo opened its Africa exhibit. One of the with occasionally grass being grown in the exhibit. There are a subsections of that exhibit is an open-air aviary. This aviary has number of large trees that have been allowed to grow through the Ihoused a number of birds and mammals over the years and one upper netting. Bamboo is the main plant in the exhibit. A con- of the residents has been a pair of Hadada Ibis (Bostrychia hage- crete pond that has been coated with a rubberized coating and is dash). The male ibis was hatched on 16 July 1992 at the Franklin cleaned by the dump/clean/and fill method is in the exhibit. There Park Zoo, Boston and the female was hatched on 14 May 1990 is a holding area that the animals can walk into as well as two at Zoo Atlanta. These ibis have been very successful in hatching small barns. out and raising offspring over the last couple of years. Information There have been numerous species housed in the exhibit over gathered from their endeavor is being presented here. the years besides the Hadada Ibis. One species of mammal has The aviary is approximately 8300 square feet of surface area been the Red-flanked Duiker (Cephalophus rufilatus). These AFA Watchbird 17 Hadada Ibis egg after a chick has hatched

duikers have been successful to spray the eggs with cooking in breeding and rearing young spray to inhibit egg develop- in the exhibit and are currently ment. This second method had housed there today. Other spe- the advantage of allowing the cies of birds which have been birds to incubate an egg and exhibited with the Hadadas not have the female constantly include Saddle-billed Storks laying eggs. Correctly colored (Ephippiorhynchus senegalen- dummy eggs were not available. sis), Spoonbills (Platalea alba), In 2009 the PMP for Hada- a Hooded Vulture (Necrosy- das made the recommendation rtes monachus), Hartlaub’s to breed this pair. Earlier in the Duck (Pteronetta hartlaubii), year some major tree work was and a variety of north Ameri- done in the exhibit. One of the can waterfowl. Currently resid- tulip trees was topped and the ing along with the Hadadas are birds made a nest on the flat Sacred Ibis (Threskiornis aeth- area. This had the added advan- iopicus), Red-crested Pochards tage of being able to view into (Netta rufina), White-faced most of the nest by climbing up Tree Tucks (Dendrocygna vidu- into a planter that was approxi- ata) and Fulvous Tree Ducks mately 30 feet away. (Dendrocygna bicolor). The ibis were left to their The Hadadas had bred once own devices and by mid Octo- in the early years but not much ber of that year we had our of the information concern- first chick. Unfortunately no ing that event was recorded. detailed records were kept with In subsequent years the Popu- regards to when the egg was lation Management Program laid and the chick hatch out. recommendation was not to Twenty-eight days after the ini- breed the birds. The birds were tial discovery of the chick, it discouraged from reproduc- fledged. ing primarily by limiting the In 2010 our first egg laid nesting materials available to hatched out after 26 days. This them as well as destroying their chick was observed being fed nest. When the nest could be and everything appeared to be reached a second method was going well. A second female

18 Volume XXXVIII • Number 4 • 2011 Parent Hadada Ibis on their nest.

Hadada was seen trying to get nest and going out onto one onto the nest. Whether she of the limbs that supports the wanted to mother the chick, nest. These chicks were slated kill it, or just get a closer look to go into our bird show (Wild- at it we don’t know. Unfor- life Live or WLL) so the deci- tunately the chick was found sion was made to catch them dead five days later. There were up before actually fledging. numerous occasions where that The main reason for that deci- female was seen fighting with sion was because of the dui- the male both around and on kers in the exhibit. Although it the nest. This female was sub would have been an easy task to sequentially removed whenever go in with a net and catch the our pair started nesting. birds on the ground, that dis- Six days after the chick turbance would have excited was found dead the pair were the duikers. With attention observed breeding. Since the being paid to catching the bird nest was already constructed, a scared duiker could easily run the female laid an egg within into the fencing and sustain the week. Thirty-three days injury. after the egg was laid the pair The chicks were given a discarded the infertile egg by physical by the vet staff. At pushing it out of the nest. At WLL, a stall was set up for that time a second egg was them. The surface of the enclo- observed on the nest. Due to the sure was asphalt covered by time frame involved it is believe sod. Wood chips were avoided that the hen laid the second egg for the fear of accidental inges- 30 or so days after the first egg. tion and impaction. Limbs Twenty-eight days after seeing were used as roosts and half the second egg, a duiker was of an animal transport kennel seen carrying around an egg- was used as a replacement nest. shell. The nest was check and a This had towels in the bottom chick observed. Two days later of it. A shallow rubber tub for a second chick was observed. drinking and bathing was pro- At 28 days of age the first vided. A larger tub that the chick was observed leaving the chicks could get into and wet

AFA Watchbird 19 themselves down was rejected, Small fish as well as some of the as they might not be able to get meat diet was also fed this way. out. They still could not fly. Hand feeding was done three Various food items (meal- times per day over a seven days worms, crickets, earthworms, period. Then the assisted feed- tiny smelt, and their meat ings were reduced in numbers diet) were offered. The meat over the next week to encour- diet and fish were left in for a age them to feed on their own. limited time so that it did not Their initial consumption each spoil. The other items were was 90g of fortified meat, 30g offered ad lib to encourage the of fish (small smelt), and 2 birds to start feeding on their earthworms. own. Weights were obtained They had a tub with meal- on a daily basis to monitor worms available for most of their progress. The birds were the day and through the night. banded with plastic leg bands, Crickets were tossed to them one white and one red. to encourage their feeding The baby ibises were behav- on their own. Both had lost ing and defecating fine but were weight initially. The chick with not observed eating much. Ini- the white leg band went from tially they needed some assisted 1040g.down to 890g. The chick feedings. The hand feeding with the red leg band went from was done by starting an earth- 1180g. down to 1040g. worm down their throat. This Nineteen days after they Hadada Ibis with chick elicited the gobble response. were removed from the exhibit

20 Volume XXXVIII • Number 4 • 2011 the birds were eating entirely destroy the nest. By that time on their own which was 45 and there were two eggs and both 47 days respectively from when of the eggs were infertile. they hatched. The birds took a hiatus On several occasions an from their reproductive activ- adult Hadada Ibis that was ity until March of the next already residing at WLL was year. Nesting material was put in with the juveniles to provided in the form of sticks encourage them to eat. This and short branches that the had the added advantage of ibis would be able to carry up allowing them to socialize with to the nest. Grass hay that was an adult bird. There seemed to used as bedding for the dui- be no interest in the chicks dis- kers was incorporated into played by the adult. Eventually the nest by the Hadadas. They however, the chicks mimicked built their nest in the same tree the adult bird in foraging as as before, continuing to make well as vocalization. observations possible. By the Twenty days after the pair end of the month they had an of chicks were removed from egg. Twenty-eight days later a the nest, the parent birds were chick was observed being fed. again sitting on an egg. Since A second egg was observed to this was late in the year (Sep- be pipping and two other eggs tember) and we did not want were seen. a chick to be raised in the win- Two days later eggshells ter, the decision was made to were found beneath the nest Hadada Ibis chick fledgling

P2012_USA_AFA_Advert_FINAL.indd 2 AFA9/09/2011 Watchbird 9:25:16 AM21 A parent Hadada Ibis stands guard with a chick on the nest. indicating that the third chick a weasel had gotten into the A few days later a second egg be seen on the chick. The chick had hatched. All three chicks exhibit, killing and consuming was laid. Thirty days after the also started flapping its wings. were observed being fed. Two the chicks. The remains of one first egg was laid, the birds On day 26, it was noted that days after being seen, the third chick were found partially con- pushed it out of the nest. It both parent birds were off of the chick appeared lifeless in the sumed and the remains of the broke on impact and smelled nest for the first time. The chick nest. Since the adults were second chick were never seen. quite rotten. No development was doing a lot more walking observed feeding it we assume A weasel had been seen on the in the egg was seen. Three days around the nest. Over the next it did not die of starvation. It premises. For several days the after that the female could not couple of days the parents spent could have been suffocated by parent birds were incessantly prod the male to leave the nest. more time away from the nest the other chicks or had some calling to the lost chick. The next day eggshells were flying up mostly to feed the other type of malady causing The reproductive urge in found beneath the nest and a chick. At this time the chick it to die. It was found under- our Hadada pair is strong; chick observed. We speculate had to do a lot more begging to neath the nest moments after within 15 days they had rebuilt that the reason the male would get the parents to regurgitate the adult pushed it out. It was the nest and were sitting on an not leave the nest is because food. The young bird would go too far deteriorated for the nec- egg. One of the behavioral cues the egg was pipping. Around out onto the limb and the par- ropsy to reveal cause of death. that we use to indicate an egg is the fifth day the chick was seen ents would call to it in a similar Three days later the nest was seeing the male bird constantly backing up and defecating over fashion as they would to a lost found destroyed and the chicks sitting on the nest (our birds are the edge of the nest. chick but without the urgency. missing. We speculate that banded for easy identification). By day 13, pinfeathers could Finally, after 37 days, the chick

22 Volume XXXVIII • Number 4 • 2011 left the nest. For the next cou- display exhibited when one of ple of weeks the parents contin- the birds wants to take over the ued to feed it. During that time duties on the nest. It will bring crickets and mealworms were to the nest either some of the tossed in the chick’s direction grass hay or small branches. It to help stimulate its feeding on will present it to the other bird its own. and then incorporate it into Both birds engage in nest the nest. building. The nest is a rel- This relief display can go atively round structure of on for several minutes with loosely lightly woven twigs and each bird clacking its beak branches. Other material such and preening the other bird. as grass hay that is available in Eventually they switch places. the exhibit is used. The nest is Hadada Ibis exhibit When a chick is present the built on a flattened portion of relief display becomes more a pruned tree. The eggs are laid measurements were taken As nest building progresses urgent with the cries of that every other day or third day on three eggshells that had the birds can be seen on the chick. This encourages the par- with there being an average of been retrieved. The incuba- nest constantly rearranging the ent with the food to prompt two but up to four in a clutch. tion period by our birds for material to their liking. When the sitting parent with its foot. The eggs are a tan color our environmental conditions this activity slows to the point Usually this is enough to get with brown spots. They are has been 28 days. Nest build- that one continuously stays the sitting parent to relinquish approximately 43 mm wide ing and breeding activity slows on the nest we can be assured its spot and the chick gets fed. and 54 mm in length. These down during our winter. there is an egg. There is a relief The diet that we feed our

24 Volume XXXVIII • Number 4 • 2011 ibis is a Mazuri meat diet that We feed the bugs in a tray throughout the yard. The male pair that were removed to par- has to be imported from Can- that has duck chow in it or usually just ignores the other ticipate in our wildlife show. ada, as it is horsemeat based. scattered fed throughout the birds. Three chicks were killed while To the meat, ground flamingo exhibit. We always feed one The adults feed the chick on the nest and one died of chow and whole flamingo of these trays in our holding regurgitated food. The chick, unknown causes. The success chow is added. Supplement area and the birds have learned as it gets older, can be observed in breeding Hadada Ibis at the calcium carbonate is mixed in to come into that area. This poking at the parent’s bill beg- Oregon Zoo has relied in part as well. All of the birds have has several advantages. There ging for food. on an excellent pair of birds access to waterfowl pellets. We are heat sources in that room After a while the parents that wanted to breed and raise feed a large number of large so that during cold inclem- relents, opens it beak and starts young no matter what the cir- mealworms as well as crickets ent weather the birds can go to regurgitate the partially cumstances. Behavior modi- to our birds. in and warm themselves. Also digested food. The chick shoves fication in various forms was The crickets are fed Fluk- when the Hadadas have chicks its beak into the parent’s beak used to help ensure the birds ers Cricket Chow, which is they will come in there and and readily accepts this gruel. success. Although this cannot high in calcium. The crickets demand their ration of bugs Eventually the chick will fledge be thought of as the definitive eat the chow, but can’t digest and earthworms. If these items and the parents will feed it on work on these ibis, it does give the calcium. This delivers a were fed solely out in the main the ground. some insight into their behav- substantial part of the dietary exhibit the other occupants of In conclusion, the pair of ior as well as some parameters calcium needs of our birds. the exhibit would get a major- Hadada Ibis since 2009 had for reproduction. The Hadadas will readily con- ity of the bugs and worms at least five eggs that did not Special thanks to Shannon sume earthworms when they first. Although we have seen hatch. The average incuba- LaMonica and Tanya Paul start laying eggs or have chicks. the female Hadada be very tion period for those that did for their notes on dealing with Other times of the year they aggressive towards the sacred hatch has been between 26 the chicks at Wildlife Live and are less enamored with the ibis, chasing and pecking and 28 days. They raised two Michael Illig for assisting in earthworms. them when bugs are scattered chicks that fledged another editing this article.

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