I have been writing about The Colour of Fish on and off since 1979. There have been several blogs on the topic since 2014.
It is generally thought that most fish lose their colours upon death, but this is not always the case. Some species seem to retain their colours or even enhance their colours in some cases.
Many photographers have been busy recording fish deaths on South Australian beaches during the 2025 algal bloom that has killed off most of our marine life.
Many of their photographs have revealed some interesting examples of colour retention or enhancement.
One such case is Andy Burnell’s photos of Blue Weed-Whiting, Haletta semifasciata. The Advertiser recently reported that Andy had found more than 500 bright blue fish dead at Marino Rocks. They had reportedly been flung ashore by a storm the day before.
According to Fishes of Australia, Blue weed-whiting males are said to be “characterized by their bluish colouration ….. Males exhibit vibrant colours during the breeding season, showcasing their beauty to attract females.”
Although Andy had been photographing dead beach-washed fish for a while, he was shocked at the extent of the numbers of dead Blue Weed-Whiting that he came across on that day. The bright blue fish tended to stand out from all of the other dead specimens to be seen.
Andy pointed out that the bright blue fish were the males of the species. After posting his photos of them online, some people could not believe that the bright blue colouration of the fish was their natural colour. They even suggested that Andy had ‘photoshopped’ the photos by either ‘retouching the colours’ or using Artificial Intelligence (AI) to enhance the colours.
The Advertiser article featured this still taken from one of Andy’s videos showing the extent of fish deaths: –
Many photographers have posted recent findings of dead Blue Weed-Whiting on iNaturalist.
Here are some of Andy’s photos that he posted on his Facebook page: –
Andy also posted some video footage of live Blue Weed-Whiting on his Crab.e.cam Facebook page.
My thanks go to Andy for his photographs.
I hadn’t realised how great a proportion of the healthy adult Blue Weed-Whiting I’ve seen as schools (mostly before the HAB) were males. Often they have looked like they’re all females (fairly drab),or with some having only a fairly subtle increase in the amount of blueness. I suppose that is expected outside of breeding season, but the photos in the Advertiser etc, by including a few obvious adult females along with the many rich blue adult males, have educated me,big time!
Thanks Andy and Steve!