THERE was nothing left of their bodies but black and white feathers, spindly bones and their oh-so-distinctive orange beaks.

Three years ago the puffins of the Bering Sea started to die. By the autumn of 2016 something like 9000 emaciated seabirds are thought to have washed up on the beaches of St Paul Island, a tiny volcanic speck of Alaska half way to Russia.

American scientists were horrified: an iconic species was starving. The puffins’ food, they said, was moved away as the once frigid waters of the north heated up.

Seabirds are like canaries in a mine, a barometer species. Their fate - like that of the mass mortalities of Pacific puffins - tell as much about the climate emergency as any researchers’ temperature graph.

Scottish scientists are now watching our own Atlantic puffins, near cousins of the critters on St Paul Island. And they are worried. Populations are dwindling.

This summer there were concerns over how many puffins were on the Isle of May in the Firth of Forth. It lost a third of its birds between 2008 and 2013. Why? As in St Paul, it is all about climate change and food.

Puffins eat sandeels. And sandeels eat tiny zoo plankton. But what if the zoo plankton are not there to be eaten?

Scientists at Marine Scotland, the Scottish Government’s fisheries protection quango, yesterday published research getting underneath the effects of global heating on the predators and prey.

READ MORE: Puffin population plummet blamed on lack of food

Sandeel larvae usually hatch close to the start of a “bloom” in their prey, the eggs of tiny crustaceans called copepods. Crudely, baby sandeels have plenty to eat. Or at least used to.

Now warmer waters seems to mean that copepods, the favourite dinner of sandeels, will not be blooming when sandeels hatch.

Marine Scotland scientists, published in Nature, look at various scenarios for sea temperature rises.

The researchers warn warmer temperatures would create a situation where the larvae hatch days after their first meal was abundantly available.

In a “worst case scenario”, the scientists said the eel larvae might fail to get enough energy from their first feed and then suffer “high mortality rates”.

Scientists call this a “trophic mismatch”, the gap between a predator being born peckish and their prey being available for them to eat.

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The study drew on data gathered by Marine Scotland’s Scottish Coastal Observatory monitoring site at Stonehaven in Aberdeenshire, and yearly winter assessment surveys conducted from a research ship.

Previous research has looked in general terms at populations of prey and predator rather than focusing on the trophic mismatch.

But, as in the Bering Sea, for most of us the most visible consequences of changing sea temperatures are in birds colonies.

It is far harder to trace moving fish or plankton populations under the waves.

Marine Scotland, meanwhile, also has trouble keeping track of one of the other factors in the health of the seas: commercial fishing.

The agency has decided to take to the skies to cover the seas. It has put out a a tender h for ready-to-fly drone systems “designed for vessel-based operations” on its three fisheries protection craft, Minna, Jura and Hirta.

It said the drones would “improve MPV [marine protection vessel] capability in monitoring activity in the marine environment, without altering or influencing the behaviour of the subject prior to inspection by a boarding party”.

The value of the contract, due to run from 23 December to the end of March 2022, is estimated at £2.5 million.

Drones were previously used by Marine Scotland a number of times between 2015 and 2017 for compliance purposes, but they were deployed in “response to a particular fishery issue which no longer requires their use”.

Marine Scotland is also looking to upgrade the three vessels with camera equipment to record fishing activity during daylight hours and also at night.

The agency hopes to be able to record footage at a relatively long distance, with thermal imaging involved.

READ MORE: Beyond Brexit: ‘Huge danger’ over-fishing will destroy fragile stocks

That contract - which is likely to run from the end of December through to 31 March 2024 - has an estimated value of £870,000.

A Scottish Government spokesperson said: “We take protection of the marine environment very seriously and these two contracts are part of our ongoing commitment to enhance our capability at sea.”

The UK was earlier this year revealed to be “the biggest culprit” in the EU for overfishing. The New Economic Foundation said more than 100,000 tonnes of fish above quotas would be taken out of British seas in 2019. Overfishing of sandeels, for example, is linked with seabird declines.