Short-tailed shearwater (Ardenna tenuirostris)

​Application for Scientific Permit – Available ​for Public Comment 

​Public comment on the following application for a Scientific Research (Fauna) Permit is open until 20 October

Applicant:

Institute for Marine and Antarctic Studies – University of Tasmania

Species/Taxon: 

Short-tailed shearwater (Ardenna tenuirostris)

Location: 

Little Green Island, Little Dog Island, Big Green Island, East Kangaroo Island, Goose Island, Cape Queen Elizabeth - Bruny Island, Cape Deslacs, Fort Direction, Wedge Island, Whalebone Point – Bruny Island, The Neck – Bruny Island

Title of research: 

Approaches to assess status of, and pressures upon, short-tailed shearwater rookeries in Tasmania

Aim of project:

This study aims to estimate the population size of short-tailed shearwater breeding across selected islands in Tasmania. The objective is to obtain up-to-date information on the status of these populations by undertaking detailed ground surveys that include fine-scale habitat description to provide essential baseline data for long-term monitoring, identify key breeding habitats, and support conservation and management of seabird colonies.

Justification: 

The short-tailed shearwater (Ardenna tenuirostris) is a highly migratory seabird that breeds almost exclusively in southeast Australia, with more than 80% of the global population found on islands in Bass Strait, Tasmania. Most colony population estimates date back to the 1990s, and no recent monitoring exists for several of the target islands. Recent findings also suggest ongoing declines in certain rookeries, leaving a critical gap in baseline data needed for conservation and management. At the same time, shearwaters are facing increasing anthropogenic pressures from climate change, extreme weather, windfarm proposal and habitat disturbance. This highlighting the urgent need for up-to-date population on key rookeries around Tasmania. 

Maximum likely numbers of individuals involved: 

Across all 11 study sites there are estimated to be up to 550,000 burrows, based on historic colony counts (Skira et al. 1996). This number reflects total colony size and does not represent the number of birds that will be directly checked. Only a small proportion of burrows will be sampled using transects or quadrats at each site to provide updated information where recent data are lacking.

Activities undertaken and methods:

Transects of approximately 100 m × 2 m will be placed across the islands to survey burrows systematically. Along these transects, quadrats may also be established to record the number of burrows, their occupancy, and habitat characteristics. Burrow occupancy will be assessed by using a method where burrows are examined by using a thin stick (with a rounded end) or by carefully placing a hand and arm if they’re deep or curved. Each burrow will be examined as completely as possible, ensure the full tunnel is checked. The check will stop immediately if resistance, pecking, or a bird is felt. Occupancy results (“bird” / “no bird”/"unknown") will be called out and recorded immediately. At the same time, evidence of activity around the burrow will also be recorded (fresh digging, feathers, faeces) together with vegetation characteristics. This approach ensures burrows are checked carefully but quickly, with minimal disturbance and no handling or removal of birds.

When required, burrow occupancy will also be checked with a burrowscope. This device consists of a small camera attached to a flexible cable that is carefully guided down the burrow tunnel toward the nesting chamber at the end of the burrow. The live image is displayed on a screen outside the burrow, allowing the observer to determine occupancy (e.g. presence or absence of an adult). 

Drone surveys will also be carried out to map vegetation cover and colony extent. Flights will only occur during daylight hours when shearwaters are away foraging, to avoid any interaction with birds and when there are no birds above ground or in the air, to avoid impact. The drone will be launched and landed outside the colony, flown at a safe altitude, and will not hover directly above active burrow areas. If any disturbance is observed, flights will stop immediately. Drone flights will be carried out by a licensed drone pilot to ensure safe operation and compliance with regulations

Fate of animals:

At no stage will animals be captured, handled, or removed from their burrows. All surveys are conducted at the burrow level only, ensuring minimal disturbance to the birds and their habitat.​

Likely impact on species involved (including any by-catch):