Spotlight on Research: Parrot Enrichment
This issue, we caught up with Joanna Berger, who recently graduated with Distinction from the University of Edinburgh’s Royal (Dick) School of Veterinary Medicine. As part of her Master’s project, Joanna traveled to Virginia to work with a parrot sanctuary called Project Perry, researching how the introduction of a new enrichment item to an aviary full of African Greys might influence different kinds of behavior. The aims of her study were to:
(1) Describe behaviours performed by the parrots at ground-level; (2) Ascertain whether they have ground-level territories; (3) Analyse the effect of the provision of an enrichment device on individual parrots and on the group as a whole; and (4) Assess whether enrichment provision results in disruption to social structure and parrot territories.
The enrichment was a metal tray filled with bark mulch, which the parrots mostly interacted with by digging and chewing. The resulting study provides a fascinating insight into how parrots that live in groups relate to one another, as well as how these dynamics ought to be considered when designing an enrichment program. Her dissertation is available through ResearchGate. We talked to Joanna about her interest in parrots, and how her research might inform behavior consultants and parrot owners.
What made you want to study parrots?
Parrots have always fascinated me—I played Polynesia, Dr. Dolittle’s African Grey parrot, in a children’s play, and I spent time visiting a feather-picking African Grey at my local animal shelter when I was a child. During my undergraduate psychology classes, I learned about Alex and Dr. Irene Pepperberg. After graduating with my bachelor’s degree in psychology, I worked as a veterinary nurse at a specialist veterinary centre for exotic animals. Many of the parrots that I cared for at the exotics veterinary centre had severe behavioral issues (feather-picking, aggression, etc.). I tried to provide environmental enrichment in the veterinary center, and I discussed parrot behavior with our clients. I read chapters in avian veterinary textbooks written by Dr. Susan G. Friedman. I took Dr. Friedman’s Living and Learning with Animals: Professional course and I attended an online lecture with avian specialist Scott Echols, DVM, about environmental enrichment, but I wanted to learn more about parrot behavior during my applied animal behavior and animal welfare master’s degree.
Why did you choose Project Perry for your research? What is the sanctuary like?
I first heard about Project Perry while attending the Humane Society of the United States “Taking Action for Animals” Conference in Washington, D.C. I also heard Project Perry mentioned while I worked at Pender (Eastern) Exotics Veterinary Center. I emailed Matt, the director of Project Perry, about doing a research project there, and he invited me to visit the sanctuary. It was amazing to see parrots in a naturalistic aviary setting. I chose Project Perry because they had large aviaries containing multiple African Grey parrots. Field studies of African Grey parrot behavior are very difficult and limited by visibility. In the Project Perry Grey aviary, I could observe 47 adult Greys in a social, naturalistic setting and see them well enough that I could identify individual birds. It was an amazing and rare opportunity to study the social and foraging behavior of this species.
Project Perry is a wonderful sanctuary with very large, naturalistic aviaries housing social groups of parrots. They are only open to the public during a single open house day once a year. The sanctuary is located on a beautiful, peaceful property surrounded by forest in a rural area. Project Perry has two African Grey aviaries and houses over 300 rescued parrots of multiple species. In March, I will volunteer to help them finish building their brand new Macaw aviary. I like their goal of being a place where birds can be birds (meaning they’re able to do things like fly and live in social groups). I visited the sanctuary and discussed the study design with Matt before beginning my research. I was fascinated by parrot behaviors that I saw in the Grey aviary that I’d never seen before, especially digging in the natural dirt floor.
Tell me a little about your design process behind the enrichment item.
I had to balance the needs of the sanctuary staff and the parrots with my research interests. My supervisors at Edinburgh University suggested that I study the effect of food locations on the social hierarchy of the Greys because similar animal welfare research had been conducted with chickens. It was not possible to change the food locations in the aviary because it would be too disruptive to the parrots and the sanctuary staff. I was really interested in preliminary observations of parrots manipulating the pieces of mulch on the aviary floor.
An early study idea was to test whether parrots preferred new mulch over the old mulch pieces that had been on the aviary floor for the past seven years. I designed the device with that in mind. I consulted with Graham Law, an expert in zoo enrichment who designed feeding poles for tigers, and he liked my idea of putting new mulch in a tray. I built the tray from stainless steel because it is a material that is indestructible (the same tray could hold the mulch during each observation period) and non-toxic to parrots. I used medium pieces of pine-bark mulch because that was the same type of mulch that was already on the aviary floor and was non-toxic to parrots.
A previous study at Edinburgh Zoo found that parrots enjoyed having bark chipping substrate, and that informed my research. The tray was deep enough to allow parrots to dig in the new mulch inside the tray. It turned out that the Greys were more interested in the metal tray itself than I thought they would be, so I decided to consider the tray and mulch as a single enrichment device unit and to study the effect of that entire device on social and foraging behavior.
Diana May’s (2001) descriptions of African Grey parrots spending time on the ground in the wild fascinated me, and I wanted to learn about ground-level behavior, so the device was designed to be moved to various locations on the ground. Susan Friedman, PhD, had discussed her concerns that “height dominance” theories of other parrot trainers were inaccurate and led to unethical training techniques. I had been chased by parrots aggressively running toward my feet across the floor of the veterinary center/bird boarding area and wanted to study dominance and aggression on the floor level because “height-dominance” was being discussed within parrot training and veterinary circles, but ground dominance was not.
You suggest that the digging you observed in the bark mulch might be a nesting behavior. Do you think parrots might respond differently to enrichment items that are designed to elicit different natural behaviors?
Enrichment items should be designed to elicit specific natural behaviors. Environmental enrichment is a “process in which changes to structures and husbandry practices are made with the goal of increasing behavioral choices to animals and drawing out their species-appropriate behaviors and abilities, thus enhancing animal welfare” (BHAG, cited in Young, 2003). I would like to conduct future research in which nesting boxes are added to the aviary and see if the presence of nesting sites causes a reduction in digging behavior. The aviary did not have any nesting sites, so the digging could have been a nesting behavior.
My study was conducted at a time of year when parrots were performing a lot of mating behavior, so I think mating social dynamics played a role in interaction with my enrichment device. However, a previous study found that Grey social structure limits access to food. I think that territories would limit access to food items and enrichment devices containing food as seen in that previous study of Greys and similar studies of other species. Anecdotally, I saw social group and territory limit access to other enrichment items in the aviary, including hanging toys on tree branches, a plastic Easter egg that the parrots balanced on, and large sticks that the parrots picked up with their beaks and banged against the floor.
What more can be done, research-wise? What will you do next?
There are very few people researching parrot behavior, and so much more research can be done. I met Donald Brightsmith at the North America Ornithology Conference during a presentation by Elizabeth Hobson on their studies of the behavior of wild parrots at a large clay-lick in Peru. Dr. Brightsmith will be researching geophagy (soil/clay-eating) at Texas A&M to try to discover more information about the nutritional needs of Quaker parrots. I’m thrilled that the World Parrot Trust was successful at the latest CITES conference and that Grey parrots have been listed as a protected species. At some point, I would love to travel to the Congo to observe Grey parrots in the wild.
I recently started an animal behavior consultancy business in Virginia, and I am hoping to apply some of the findings of my research to help pet parrots living in homes. I will be presenting my dissertation research at the Animal Behavior Management Alliance conference at the Cincinnati Zoo in Ohio in April 2017. I’m giving talks about animal behavior at veterinary hospitals and schools to help share my knowledge of applied animal behavior science. I want to share my ethograms of parrot behavior to help people understand pet parrots.
One of the birds in my study (who had a history of neglect) performed more self-grooming and depressed inactive behavior before I presented the enrichment device to him. After presenting the enrichment device, he interacted with the mulch and interacted socially with other birds. I would like to see if a container of mulch can be used as an inexpensive enrichment option for parrots inside houses or cages. I’m also interested in studying feather-picking behavior and treatments in more depth, possibly as a PhD. I have heard that there is some research being done on this topic at Utrecht and Auburn Universities.
Do you think behavior consultants ought to consider suggesting the addition of another bird as part of a plan to improve overall welfare?
Yes. Social enrichment benefits parrots (Garner et al., 2006; Meehan et al., 2003; Nicol and Pope, 1993). Parrots are very social animals and live in flocks of thousands in the wild. Of course, I would always urge clients to think adoption first if they are considering adding another bird because many, many pet parrots are relinquished to sanctuaries, rescues, and shelters each year. I’d recommend having your parrot DNA sexed and finding a second parrot that can become a mate for your bird because most parrot species are monogamous and mate for life. Homosexual pairs and triads of parrots have been observed, but male-female mated pairs are most common.
I know a behavioral case study of a Macaw who developed severe behavior problems (severe feather-picking and biting aggression) after her Macaw mate died. She now lives in an aviary with other Macaws like the Grey aviary in my study and her abnormal behaviors have disappeared. I saw parrots benefit from social interaction with other birds during my study, and Matt Smith told me that abnormal behavior often decreases when parrots are moved into the aviary social setting.
Do you think companion parrots that live in human homes might have perceptions about territory that their owners should know about? How might we find that out?
Yes. I absolutely think that parrots who are “cage-aggressive,” “cage-bound,” or aggressive toward their owners likely have perceptions about territory that the owner is accidentally violating. Adult parrots are territorial around their nest sites during mating season.
I noticed that parrots like their personal space when interacting with one another. If you haven’t had the opportunity to observe parrots in a group setting, you can watch crows and starlings as they perch in trees and on power lines to get an idea of how bird social behavior works. Crows and starlings sit specific distances from one another in the tree or on the power line. Mated birds sit closer to each other. When a new bird arrives, s/he won’t land at random, but the birds will rearrange themselves according to their social structure. Only mated or very closely affiliated parrots groom each other.
Personal space is negotiated through chasing and fleeing interactions. Highly aggressive behavior between Greys was extremely rare during my observations. I only observed one single instance of a parrot biting another parrot, and that was during my preliminary observations, not during my actual study. As with dogs, there are many subtle behaviors and body postures that parrots do to show us they want some space before they bite us. We often miss all of those subtle behaviors because we don’t understand them or aren’t watching for them.
Here is my ethogram of parrot social behaviors:
|Chase||Low-intensity agonistic behavior, walking toward a conspecific, displacing a conspecific|
|Flee||Low-intensity agonistic behavior, walking away from a conspecific, retreating, being displaced by an approaching conspecific|
|Stick-bang||Lifting a large stick with beak and repeatedly and rapidly lowering head and body to strike the stick against the ground, in what appears to be a display of strength|
|Head-bob||Repeatedly moving head in an up-down motion|
|Neck-fluff||Piloerection of the feathers on the neck while lowering head, usually while approaching another individual during an agonistic displacement interaction|
|Bow||Piloerection of feathers on body, raising both wings above back so that shoulders are close together, extending tips of wings, and leaning toward ground with body, usually rhythmically and in unison with a conspecific|
|Allogroom♥||Affiliative behavior in which the beak is used to groom and preen the feathers of another individual|
|Kiss♥||Affiliative behavior in which two individuals lock beaks and may regurgitate|
|Mate♥||Affiliative behavior involving mounting, placing feet on top of an individual’s back, presenting and displaying cloaca, cloacal contact, vocalizing with repetitive wheezing sound, lifting one wing at a time while another individual moves rhythmically beneath the lifted wing or moving in this way beneath the wings of another individual|
Table 1. Ethogram of African grey parrot ground-level social behavior. Affiliative behaviors are denoted with a heart (♥)
If there are multiple parrots in the home, we need to be aware of territorial disputes between birds over desirable resources. I recently saw a video shared by a parrot owner on Instagram that I knew was territorial behavior. Two Macaws were standing on a blanket. I could tell the Macaws were having a territorial dispute over the blanket because their interactions looked like the Grey interactions around my enrichment device. The owner thought they were playing, but a few other parrot owners and I commented that it looked like a territorial dispute and I recommended that she give her birds a second blanket. Make sure all parrots in your home have their own toys because they might not share them unless they are a mated pair.
If you need to take a toy away from a parrot, you should trade it for something more desirable (like a delicious food treat) to reduce territorial issues. Every home is unique, so an animal behaviorist should do an assessment of the environment in the home to help reduce issues of territorial aggression.