Tougher measures to protect Scottish salmon from a devastating parasite have been called for by MSPs.
The salmon fishing industry in Scotland faces the parasite threat
Holyrood's environment committee wants to see tighter port controls and a campaign to raise public awareness of the Gyrodactylus salaris (GS) parasite.
It has never reached the UK but has previously wiped out stocks in Norwegian rivers.
GS could be brought into the country by fish from infected areas, or even from the waders or rods of fishermen.
Gyrodactylosis, caused by the GS parasite, is a serious fish disease that infects the skin, gills and fins of salmon, trout and some other species of freshwater fish.
Barely visible to the naked eye, the parasite can nonetheless cause serious damage to some UK strains of Atlantic salmon. However, it has no impact on human health.
If the GS parasite were to be introduced into UK waters, entire river systems could quickly become infected, resulting in the decimation of valuable freshwater stocks of salmon, both in the wild and in aquaculture.
Scotland is the third largest producer of Atlantic salmon in the world, employing an estimated 10,000 people and millions of pounds of compensation could be paid out to farms in the event of an outbreak.
The Aquaculture and Fisheries Scotland Bill, which is currently going though Holyrood, contains measures to prevent the parasite's march.
Holyrood's environment committee has said the scale of escapes of Scottish farmed fish means that the parasite could devastate wild salmon, necessitating the chemical treatment of rivers.
Members are calling for more robust port controls and a campaign to encourage users of angling and other water sports equipment to disinfect their gear.
Committee convener Sarah Boyack gave her support to the bill.
However, she expressed reservations about some of the methods which have been put forward.
She said: "We recognise that GS could devastate Scotland's salmon [angling] industry and agree that action must be taken to address this threat.
"The chemical measures used to tackle the parasite, however, could have a huge effect on biodiversity and other water users, including the whisky, leisure and renewable energy industries.
"The committee found it difficult to come to a fully formed view on the wide-ranging powers in the bill on this issue because of conflicting views on how eradication measures could affect Scotland's water courses and other industries reliant on water supplies."
Green MSP Eleanor Scott said her party was broadly supportive of the bill but believed it should go further.
The Highlands and Islands MSP added: "It's right that the aquaculture industry's voluntary code of good practice is enshrined in law and we want the statutory code to reflect best practice rather than merely the lowest common denominator.
"However, given the harm that fish farm escapes can cause in terms of chemical and genetic pollution to wild stocks, the executive should have introduced a strict liability regime to ensure farms take all steps possible to prevent them.
"With nearly two million farm salmon escaping in the last six years, it's clear that changes are needed - so this is a missed opportunity."