As subjects in criminal investigations go, sharks probably aren't the first things that come to mind.
But for Seattle-based Australian forensic specialist Jenny Giles, the ocean's top-order predators are central to her work investigating the illegal global trade in shark fin.
Geelong-born Dr Giles works with America's National Oceanic and Atmospheric Administration, where her CSI-style approach can see her called upon as an expert witness in court.
Where illegal trade in shark fins is suspected, her job is to identify the species the fin came from. The problem is it doesn't always look like a fin. Sometimes it looks like noodles. Other times, the skin has been removed exposing the fin's tightly packed internal fibres.
In this processed state, science plays a crucial role in identifying the species by using forensic genetics and DNA.
Wildlife forensic science is one of the main reasons Dr Giles moved to Seattle in 2014. When it comes to shark fins she is considered one of the discipline's pioneers, as an expert in both identifying intact fins based on their appearance and using DNA to identify processed fins being traded illegally on the international market.
"As it gets traded, often around the world, it is modified," Dr Giles said. "And by the time it reaches the consumer the skin and cartilage has typically gone."
The fin goes from looking like it did when attached to the animal to a collection of collagen-elastin fibres that resemble vermicelli noodles.
This is where forensic analysis becomes a key tool in identifying the species, which is crucial before taking a case to court.
Earlier this year Dr Giles gave evidence in what became the first conviction under California's shark fin ban.
American shark fin wholesaler Michael Kwong was convicted in March after authorities raided his San Francisco warehouse in January 2014. There they found almost one tonne of shark fin. Valued on the black market at more than $US1 million ($1.4 million), some fins were still whole, while others had been heavily processed.
As the chief forensic analyst on the case, it was Dr Giles' job to establish whether some of the material was shark fin and if there were any species listed internationally under the CITES convention or nationally under America's Endangered Species Act. There was. Among the haul were whale shark, basking shark, great white shark and sawfishes.
"This case had material ranging from big, intact basking shark fins, which had the skin on, to collagen-elastin fibres in a bag," Dr Giles said.
California is one of 10 US states, including Washington and Oregon, to toughen regulations on the consumption and trade of shark fin over recent years.
In Australia, which is a signatory to the CITES convention covering the international trade of endangered plants and animals, the 15 listed sharks and ray species are subject to strict import and export rules.
However, Dr Giles said laws regulating the international trade of listed species were not easy to enforce, even in Australia.
"Fins from listed species are difficult to detect among otherwise legal shark fins, especially when they have been modified," she said. "To enforce these laws, agencies need the resources to check for illegal material and routine access to forensic expertise, which is challenging without a federal wildlife forensic lab."
Dr Giles, who completed her PhD in shark biology and population genetics at the University of Queensland, said moving to America was the best way she could gain experience in shark fin forensics.
"In Australia we haven't yet had the resources for a co-ordinated effort [between agencies] for forensic analysis in wildlife law enforcement that's anything like what's going on in the US," she said, adding she hoped ultimately to bring her experience home.
Fairfax Media travelled to America as a guest of the Department of State Foreign Press Centre.