Cassowaries on eastern Cape York Peninsula

Cassowaries in Cape York Peninsula are dependent on the isolated rainforest remnants that are interspersed with open savanna and other dry vegetation types in the landscape.

As such, cassowaries are known to occur at various rainforest locations along the eastern Cape York Peninsula from the Lockerbie Scrub (Northern Peninsula Area), south to Kutini-Payama National Park (Lockhart River region) and the McIlwraith Range (west of Coen).

Compared with their southern counterparts - the Wet Tropics cassowary sub-population, we know very little about the Cape York cassowary sub- population.

To enable an informed assessment of the conservation status of the cassowary in Cape York Peninsula we urgently need information on where they occur, how many there are, their ecological requirements, and the relative impact of threats.

Recognising these fundamental data needs, a collaborative research project was developed in 2020 between the Ngana Malngkanichi Pama (CNCRM) Aboriginal Corporation (representing the Umpila Traditional Owners), independent cassowary researcher Wren McLean, and Cape York NRM.

Umpila Country occurs on the coastal lowlands of the McIlwraith Range where closed canopy forest habitat occurs mainly along watercourses in narrow riparian strips adjacent to dry savannah country.

During the late dry season of 2020, the Cassowary Team deployed remote camera traps with visual lures and sign surveys to detect the presence of the cassowary.

These motion-activated cameras were positioned within the Nesbit, Chester and Rocky river systems in locations where either cassowary signs were found, or adjacent to the small retracting pools of water on the river edge.

Due to their large body size and dark colouration, cassowaries need to drink regularly throughout the day.

The specific aims of this survey were to:

• determine cassowary distribution across suitable habitat in the coastal lowlands

• individually identify photographed cassowaries (for abundance estimates)

• conduct sign surveys (dung, tracks, sightings, feathers and vocalisations)

• identify threats to cassowaries and their habitat

• train Umpila Traditional Owners in the cassowary survey techniques.

A second field trip to retrieve the camera data occurred approximately 50 days after camera deployment.

The results were exciting! Together we walked for almost 20 kilometres throughout Umpila Country and found 23 cassowary signs (9 dungs, 13 sets of footprints and 1 sighting of a sub-adult).

In addition, the motion activated camera traps photographed 3 individually identifiable adult cassowaries, one sub-adult and three stripy chicks.

Unsurprisingly however, threats to cassowaries were also recorded by the camera traps; 47 capture events recorded a minimum of 54 individual feral pigs and 43 capture events recorded a minimum of 26 individual cattle.

These on-ground surveys produced evidence of a breeding cassowary population in the coastal lowlands of the McIlwraith Range and were an invaluable opportunity for the Umpila Traditional Owners to reconnect with Country and for future planning and management.

The persistence of cassowaries in this location is dependent on the health of the riparian rainforest vegetation and the availability of rainforest fruit. Feral pig abatement is a high priority for long-term cassowary conservation in the area.

Feral pigs compete for critical cassowary food resources and have a host of negative impacts on rainforest vegetation. On-ground works to address key threats will be the focus of our next work together (late dry season 2021).