2.1 Subjects and Setting
Prior to implementation, the study was approved through the University of Adelaide Animal Ethics Committee (S-2023-016). Two Southern cassowaries at Adelaide Zoo in Australia were the subjects for observations (see Fig. 1). Martina was 7 years old, and Jeffery was 10 years old at the time of observations. Martina was born at Gorge Wildlife Park and was transferred to Adelaide Zoo on the 12th of October in 2016, while Jeffery was transferred from Perth Zoological Parks Authority to Adelaide Zoo on the 4th of October in 2013.
The cassowaries had three separate habitats of differing sizes (Yard 1: 64.47m2, Yard 2: 141.15m2, Yard 3: 357m2) that they were rotated through weekly. Yards 1 and 2 were attached, giving simultaneous access to each area. Yard 3 was separate from the two other areas with no direct access to Yard 1 or 2. Each yard had access to visitors as well as secluded areas to retreat and access to a sheltered area containing a water trough and food. The cassowaries were fed twice a day, once in the morning (Approx. 08:30 h) and once in the evening (Approx. 16:30 h). The cassowary’s species-typical natural diet was created by the zoo’s nutritionist, which consisted of seasonally available fruit and vegetables such as peas, pears, apples, bananas, and spinach, as well as an insectivore mix and protein such as egg, pilchard, or day-old chicks. The cassowary enrichment program consisted of habitat rotations, Paper Mache balls or hay bags filled with fruits, as well as occasional scatter feeds. Visitors had access to the front of Yard 2 and 3 approximately 1.5m from the fence line, with the back and right side of the habitat only available to staff. Each yard was adorned with foliage, logs, moss, and trees as well as having a reserved area for a wallow which was not filled due to management reasons for the duration of this study.
2.2 Materials
Handheld Apple iPads® were assigned to each observed involved in the study. ZooMonitor (Wark et al., 2019) was used to collect all data on each iPad.
2.3 Data Collection and Procedure
An ethogram was designed from initial observations and behaviors described by the Australasian Society of Zookeeping and San Diego Zoo (Biggs, 2013; San Diego Zoo, 2023). A total of 16 behaviors were divided into seven categories (see Table 1). Additionally, a habitat map depicting the three yards that the cassowaries were located was created on Microsoft Publisher®. The ethogram and habitat map were input into ZooMonitor to collect all data.
Table 1
An ethogram for cassowaries depicting 16 different behaviors split into seven distinct categories (active, foraging, social, groom, inactive, abnormal, other), accompanied by the acronym and definition of the behavior.
Behavioral class and behaviors (abbreviated) | Definition |
Active |
Locomotion (Lo) | Directed non-repetitive movement. |
Manipulating Object (MO) | Contact with a non-edible object, with any part of the body, manipulating its position. |
Foraging |
Eating/Drinking (ED) | Beak contact with anything edible including water. |
Enrichment Interaction (EI) | Contact with an enrichment device. |
Pecking (Pe) | Using beak to contact anything inedible in a repetitive manner. |
Social |
Interacting w/ Other Animal (IOA) | Any physical contact to another animal. |
Vocalization (Vo) | Producing noise from the beak (e.g., growls, squawks). |
Groom |
Preening/Scratching Body (PSB) | Using beak to sort through own feathers or using claws to rub against body. |
Bathing (Ba) | Submerging at least half of own body underwater and using beak to interact with body of water. |
Inactive |
Laying Down (LD) | Most of body on ground with legs in front of body or tucked underneath body. |
Standing (St) | Standing with no movement, 1 or 2 feet on ground. |
Abnormal | |
Repetitive Behavior (RB) | Repeated pattern of behavior (e.g., pacing). |
Coprophagy (Co) | Beak contact with excrement. |
Other |
Defecating (De) | Excreting waste through cloaca. |
Out of Sight (OS) | Not visible to observer. |
Other (Ot) | Engaged in a behavior not listed. |
Behaviors were mutually exclusive, and the ethogram was exhaustive to ensure all possible observations could be recorded. Five university undergraduate research assistants were trained in cassowary observations by the advising author (EJF) and collected all data. Observations were undertaken at varying times of the day between 09:00h to 17:00h.
Instantaneous (pinpoint) sampling and scan sampling (Altmann, 1974; Bateson & Martin, 2021; Brereton et al., 2022) were utilized. Sessions of one hour with intervals of 60 seconds were implemented over a period of two months (August 17, 2023 – October 12, 2023), where both location and behavior were recorded. Any sessions that were less than 45 minutes were not included in the analyses. A total of 66 hours of observations per cassowary were recorded with a total of 3,960 observations per bird. Activity budgets were used to interpret the average occurrence of each behavior category and heat maps derived from ZooMonitor (Wark et al., 2019) were used to visualise activity patterns and habitat use. Shannon’s Diversity Index (Brereton & Fernandez, 2022b) was used to calculate behavioral diversity by the following equation.
2.4 Statistical Analyses
Microsoft Excel® was used to initially compile all data and produce descriptive statistics. ZooMonitor was used to create enclosure use heat maps. SigmaPlot, version 14.0 (Systat Software Inc., San Jose, CA, USA) was used to create ethogram activity and behavioral diversity graphs, as well as run their statistical analyses. As the data failed normality for activity and behavioral diversity, Mann-Whitney U tests were used to analyse the data. Due to multiple comparisons, the p-value was set at 0.00625 with a Bonferroni adjustment (0.05/8). Each behavior class within the activity budget (seven) and behavioral diversity were compared and analysed between the cassowaries for significant differences.