Silver gull harassment of humpback whales in Exmouth Gulf, Western Australia

Philippa Harkness, Kate R. Sprogis

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)


We share observations of silver gulls (Chroicocephalus novaehollandiae) harassing humpback whales (Megaptera novaeangliae) in Exmouth Gulf, Western Australia, between August and October in 2018 and 2019. Sixteen events were recorded of gulls pecking at the skin of 16 mothers and 2 calves resting on the surface. Data were collected opportunistically from a research vessel covering 5474.2 km (565 h). Events were documented through photographs and unmanned aerial vehicle video recordings and persisted for an average minimum time of 20.73 min (range 2.50-46.85 min). At least one event of a gull consistently gouging in a pre-existing lesion was recorded on a mother. Changes in behavioural activity from the whales, which varied from slipping under the surface to travelling and performing instantaneous behavioural events, were observed in 94% (15/16) of events. These are the first known records of birds attacking humpback whales. The results are comparable to early events of kelp gull (Larus dominicanus) harassment of southern right whales (Eubalaena australis) off Península Valdés, Argentina, where events have escalated over the past 50 years to consistent attacks on the whales' skin and blubber. Future research is required to monitor the trajectory of these interactions to inform management.

Original languageEnglish
Pages (from-to)584-592
Number of pages9
JournalMarine and Freshwater Research
Issue number4
Publication statusPublished - Mar 2021
Externally publishedYes


Dive into the research topics of 'Silver gull harassment of humpback whales in Exmouth Gulf, Western Australia'. Together they form a unique fingerprint.

Cite this