A seagull died after being "attacked with a spade" in Lyme Regis, prompting an RSPCA appeal for information.
The incident, which the animal charity has described as "shocking" happened in Dorset on 9 August at around 7pm.
Eyewitnesses took the animal to the vet after the attack, but it had to be put to sleep due to the severity of its injuries.
The RSPCA has now released images of a man they want to speak to in connection with the incident.
Animal Rescue Officer Dean Wilkins said: "It’s never acceptable to attack an animal with a weapon.
“This was during the school summer holidays so we’re appealing to anyone who was in the area at this time and witnessed this, or who recognises the man in the picture who may be able to help us further.
"The man, who was wearing sunglasses, a purple t-shirt and shorts, was with a group of people having a barbecue on August 9 at around 7pm.
"All wild birds are protected under the Wildlife and Countryside Act 1981 and it is illegal - except under licence - to intentionally take, injure or kill wild birds or interfere with their nest or eggs."