Coraciiformes TAG
 

Coraciiformes Taxon Advisory Group -

Breeding the Blue-crowned Motmot at Riverbanks Zoo and Botanical Garden

by Elizabeth Prouse
First Published in The Avicultural Magazine Vol. 109 No. 4
Copyright © 2003 Avicultural Society, Published with Permission

The Blue-crowned Motmot (Motmotus momota) is a beautiful, arboreal bird that has a rather large, robust body with large areas of bright green and blue plumage. The descriptive part of the common name comes from the crown of brilliant blue feathers that adorn its head. However, its most distinctive feature is the long, racquet-like tail that strikes back and forth like a pendulum and often pauses at the height of each swing. This peculiar behaviour serves as a form of communication and is usually accompanied by a faint "tick-tock" vocalization. Its range covers most of Central and South America, from humid rainforests to arid, evergreen woodlands. It also frequents plantations, orchards, and even coastal beaches. Fortunately, most of its native land is protected, and it is not threatened.

The Blue-crowned Motmot is a popular zoological exhibit. Zoos of the American Zoo and Aquarium Association (AZA) currently maintain a total population of about 80 of these birds, all of which arc managed through an AZA approved studbook. Based on these data, birds can be selectively paired through a Population Management Plan to help maintain the genetic diversity of the population.

Aviary design

The Bird Conservation Center (BCC) at Riverbanks Zoo is home to a genetically valuable pair of wild-caught Blue-crowned Motmots. Both birds were acquired from separate sources in 2000 and moved to the BCC in 2001. Neither of these birds had bred in captivity, making any offspring they produced an important addition to the managed population. The pair is housed in an indoor aviary that is 15ft long x 3ft wide x 8ft high (approx. 4.5m long x lm wide x 2.4m high). The aviary is one of 28 enclosures that comprise the BCC. All have concrete floors and are well lit by several rows of fluorescent lights. The tubes are the standard white type, rather than the full-spectrum lighting of the type used for plants and aquaria. However, clerestory and large windows along the walls allow exposure to natural sunlight. To optimize breeding, a temperature of 75°F (23.9°C) and up to 80% relative humidity is maintained year-round.

Our birds are provided with fresh food twice a day. This consists of chopped fruit covered in Marion Zoological Tropical BitsTM pellets, hardboiled egg, Hills Science Diet Canine MaintenanceTM kibble (soaked overnight) and Nebraska BrandTM bird of prey meat. Livefood such as earthworms, large mealworms and 1in. (26mm) crickets are also provided. The crickets and mealworms have for several days before use been fed a diet of Purina Game Bird Chow®. This chow is high in calcium and helps ensure that the livefood achieves a more balanced calcium to phosphorous ratio (2:1), as well as improving the overall nutritional content. Motmots do not usually drink from or bathe in standing water. Therefore, they benefit from a short misting with the water hose every day to help keep them clean and well hydrated.

Artificial nest tunnels

Even with the favourable artificial climate we have created, it was doubtful that a pair of wild-caught motmots could be persuaded to breed in an enclosure of the type described above. In the wild, motmots dig a tunnel in the forest floor or the embankment of a stream, and this leads to an underground nesting burrow. The concrete floor of the aviary met none of the motmots' breeding requirements. Nevertheless, the birds expressed a desire to nest by excavating soil from the large potted plants that furnished the aviary.

Eager to accommodate their nesting needs, keepers gathered a few ideas from other zoos and designed an artificial nest site comprising three tunnels which terminate at a nest-box. Built entirely within the aviary, the tunnel system occupies about 15% of the space. The tunnels are made of 5in (approx. 13cm) diameter corrugated drainage pipes of the kind used for landscaping. The pipes are attached to a ½in thick x 4ft high x 3ft wide (approx. 7mm thick x l.2m high x 1m wide) piece of plywood positioned vertically and fixed across the aviary. The plywood is covered with mesh and impregnated with coloured stucco to give the appearance of a mud bank. Tree roots have been inserted into the fake mud to provide perches and complete the effect. The drainage pipes extend from the artificial mud bank to the wooden nest-box which measures 1ft x 1ft x 1ft (approx. 30cm x 30cm x 30cm). The box is fastened to the back of the aviary at a level which creates only a slight downward slope of less than 1in (25mm) per foot (30cm), from the tunnel entrance to the end of the tunnel. Two of the tunnels, each 3ft (almost 1m) in length, merge into one tunnel at a Y-shaped junction, before connecting to the front side of the box. The third tunnel is 5ft (approx. 1.5m) long and bends at an angle of 90° before connecting to the adjacent side of the nest-box. Therefore, three tunnels start at the artificial mud bank, but only two terminate at the nest-box. All three tunnels are supported by a 2in x 4in (approx. 5cm x 10cm) wood frame and secured with cable ties.

The three pipes are suspended at mid-height in the aviary, allowing the birds to utilise the airspace above them while at the same time accommodating the daily routine of hosing and disinfecting the concrete floor beneath them. In fact, the birds are undisturbed by the hosing of the floor during which one of them remains in the tunnel system. When we first installed the pipes, both birds spent a lot of time perched on them, essentially hidden from view. To prevent this, the tunnel system is completely enclosed.

All three tunnels were packed with a mixture of 90% damp top soil and 10% sand. This was packed into the tunnels from the front (through the artificial bank) and tamped in with a blunt stick. The tunnels were not completely filled, but sufficient quantities of the mixture were used to provide the semblance of an earthen bank. The nest-box had been partly filled with soil when we installed the tunnel system. A large potted ficus tree was placed in front of the artificial mud bank to give the birds a much needed sense of privacy. Indeed, the tree was so large it almost filled the aviary.

Following the birds' temporary removal for completion of the tunnel system, the pair was returned to the aviary. On the first evening the pair began digging in the far left tunnel. Within a week, all three tunnels had been excavated. The birds travelled in and out, rarely exiting by the same tunnel by which they had entered. Then, as abruptly as they had started, they stopped digging. The birds ignored the burrows. seemingly having become disinterested in nesting.

The pair was observed sitting beside its apparently abandoned nest burrow for one month before it was noted one day that the female was missing. We now know that she had disappeared into the nest to begin laying her first clutch of eggs. It is not uncommon for motmots in the wild to prepare their burrows in September-October, several months before nesting, which usually occurs between February-June. This is thought to be because the ground is so much softer in the wet season than in the dry breeding season.

Incubation and chick rearing

Blue-crowned Motmots usually lay between two and four white ,rounded eggs, but may lay as many as five. Incubation is shared equally by both sexes. The male was observed to be sitting during the day, while the female took the evening shift. Consequently, they also ate in shifts. Throughout the incubation the two birds were rarely seen together. There was always one in and one out of the tunnel. Then, on the 18th day of incubation, a significant change was observed in the pair's behaviour. Both parents disappeared for several minutes at a time, spending most of this time together inside the nest. It appeared that at least one chick had hatched. The following day, however, they spent most of their time outside the nest and we began to question whether any chicks had actually hatched?

We were soon reassured when food consumption increased. The preferred rearing food was pinky mice, but 1in (25mm) crickets, medium-sized mealworms, and earthworms dusted with calcium carbonate were also eagerly accepted. As they fed frequently, fresh food was offered every two hours throughout the day. During the first week, both parents took 10-15 pinky mice daily, beating them on a perch or the concrete floor before delivering them to the chicks, They began feeding small amounts of fruit on day 13. Soon thereafter, pinky mice and livefood consumption doubled and we became unsure of how many mouths were being fed. On day 24, food consumption dropped significantly as the parents withheld food to encourage the chicks to fledge.

The first chick fledged at 28 days of age; a second chick followed one day later. Both were healthy, were brilliantly coloured and could fly surprisingly well at their first attempts. They had slightly thinner bodies than their parents and had almost identical plumage to that of their parents, the only obvious difference being their short, stubby tails.

The two young motmots were extremely timid and easily frightened. As it is easy for young birds to permanently injure their bills and damage flight feathers if they collide with the wire mesh or other objects, the keepers approached the aviary very carefully when cleaning and feeding; and for the first few days we did not clean the floor.

The chicks weaned quickly. Two weeks after fledging, they were separated from their parents and assigned separate enclosures that had been prepared in advance. Each was well planted and provided plenty of hiding places. The wire mesh was covered with EnkamatTM (a plastic erosion control material used in landscaping) to protect the birds from potential collisions with the wire mesh. Their plumage remained in excellent condition and over several weeks their tails grew to the same length as those of the adults. As their tails brushed against the foliage and perches, a small section of weak barbs near the tips of their tails broke off, leaving the racquet-shaped tips for which motmots are so well known.

A second pair of Blue-crowned Motmots has since bred in the natural-like setting of The Birdhouse at Riverbanks. This pair dug a burrow in the soil floor of the South American exhibit and followed the same behavioural patterns as the pair that bred in the BCC. While both breedings are notable, the breeding in the BCC is more significant in our estimation because the pair bred successfully in a small, indoor, concrete-floored aviary. In view of this, it is our opinion that almost any facility has the capability to breed this species.

Acknowledgements

I would like to thank all the members of the Bird Department for their considerable help in the preparation of this article.

Elizabeth Prouse is a Bird Keeper at Riverbanks Zoo & Botanical Garden,
P0. Box 1060 Columbia, South Carolina 29202-1060, USA.
Website: www.riverbanks.org