Study: Warmer Water is Pressuring Scottish Shags

Scottish Shag (Phalacrocorax aristotelis)

Scottish Shag (Phalacrocorax aristotelis). By Andreas Trepte (Own work) [CC BY-SA 2.5], via Wikimedia Commons

Guest essay by Eric Worrall

A new study claims that Scottish sea birds are being forced to diversify their diet by a shortage of their favourite prey species. But in my opinion the study ignores other issues, such as chemical pollution and long term radioactive contamination in regions adjacent to the study location.

Warmer water signals change for Scotland’s shags

Three decades of data from the Isle of May, off Scotland’s east coast, found that the proportion of sandeels – the bird’s usual fayre – declined by 48% between 1985 and 2014. Over the same period, the number of other fish prey in the diet increased, from an average of just one species per year in 1985 to eleven in 2014.

The North Sea is one of the most rapidly warming marine ecosystems on the planet, and warmed by 0.037 degrees Celsius per year between 1982 and 2012. Lead author, Richard Howells, explained that the study, “ties in with many observations of changes in the abundance, distribution and phenology of many species in the North Sea, and a decline in the availability and size of sandeels.

“Climate models predict further increases in sea surface temperature and weather variability in the region, with generalisation in shag diet, one way in which this species appears to be responding to this change.”

Short-term weather conditions also impacted on the bird’s ability to feed, with “windier conditions on a daily basis linked to fewer sandeel in the diet. This may affect the ability of parents to successfully feed their chicks,” Howells said.

”Changes in the prey types consumed by this population suggest that adults may now be hunting across a broader range of habitats than they did in the past, such as rocky habitats where they can find the Rock Butterfish. Such changes may alter interactions with potential threats, such as small-scale offshore renewable developments.”

Read more: https://www.ceh.ac.uk/news-and-media/news/warmer-water-signals-change-scotland’s-shags

The abstract of the study;

From days to decades: short- and long-term variation in environmental conditions affect offspring diet composition of a marine top predator

Richard J. Howells, Sarah J. Burthe, Jon A. Green, Michael P. Harris, Mark A. Newell, Adam Butler,
David G. Johns, Edward J. Carnell, Sarah Wanless, Francis Daunt

ABSTRACT: Long-term changes in climate are affecting the abundance, distribution and phenology of species across all trophic levels. Short-term climate variability is also having a profound impact on species and trophic interactions. Crucially, species will experience long- and short-term variation simultaneously, and both are predicted to change, yet studies tend to focus on only one of these temporal scales. Apex predators are sensitive to long-term climate-driven changes in prey populations and short-term effects of weather on prey availability, both of which could result in changes of diet. We investigated temporal trends and effects of long- and short-term environmental variability on chick diet composition in a North Sea population of European shags Phalacrocorax aristotelis between 1985 and 2014. The proportion of their principal prey, lesser sandeel Ammodytes marinus, declined from 0.99 (1985) to 0.51 (2014), and estimated sandeel size declined from 104.5 to 92.0 mm. Concurrently, diet diversification increased from 1.32 (1985) to 11.05 (2014) prey types yr-1, including members of the families Pholidae, Callionymidae and Gadidae. The relative proportion of adult to juvenile sandeel was greater following low sea surface temperatures (SSTs) in the previous year. In contrast, the proportion of Pholidae and prey richness were higher following high SST in the previous year. Within a season, the proportion of sandeel in the diet was lower on days with higher wind speeds. Crucially, our results showed that diet diversification was linked to trends in SST?. Thus, predicted changes in climate means and variability may have important implications for diet composition of European shags in the future, with potential consequences for population dynamics.

Read more: http://www.int-res.com/abstracts/meps/v583/p227-242/

My biggest issue with this study is that the authors are calling climate, based on data from just one location.

But delving deeper, there is another problem;

Environmental covariates

Annual sandeel proxies

As there are no long-term abundance data for the local sandeel population upon which Isle of May shags feed, we utilised 3 environmental proxies of sandeel availability.

Sea Surface Temperature (SST): SST affects sand-eel recruitment via the bottom-up effects of temperature on the availability of key copepod prey (Wright & Bailey 1993, Arnott & Ruxton 2002, van Deurs et al. 2009). Monthly SST data were obtained from the German ‘Bundesamt fur Seeschifffart und Hydro- graphie’ (www.bsh.de). Following Frederiksen et al. (2004), we calculated the mean of February and March SST for an inshore area surrounding the Isle of May (bounded by ca. 56°0’ to 56°4’N, and 2°7’ to 2° 3’ W), overlapping with the summer foraging range of this population (Bogdanova et al. 2014).

Calanus abundance: calanoid copepods, in particular the eggs and nauplii of Calanus finmarchicus, are of key importance to survival probability of early life stages of sandeels (Macer 1966, Arnott & Ruxton 2002, van Deurs et al. 2009). We analysed 1597 samples from the continuous plankton recorder (see Reid et al. 2003 for an overview) taken from a bounding box surrounding the Isle of May (55° to 58° N, 3° 0° E), between 1984 and 2014. This box is larger than the summer foraging range of the study population, but ensured there were sufficient data for the analysis. We included 2 measures of Calanus: C. finmarchicus (stages V to VI) abundance (as a proxy for C. finmarchicus egg production; van Deurs et al. 2009) and Calanus nauplii abundance (for all species combined, as species-specific abundances were unavailable). For each measure, we calculated mean monthly abundance from February to May, since these months constitute the principal period of larval sandeel feeding (Wright & Bailey 1996, van Deurs et al. 2009).

Lagged covariates: the abundance of 1+ group sandeels is dependent on conditions experienced as 0 group fish in the previous year (Arnott & Ruxton 2002). We therefore considered SST, C. finmarchicus (stages V to VI) abundance and Calanus nauplii abundance lagged by 1 yr as indices of the abundance of 1+ sandeel in the current year.

Read more (full text, p230-231): http://www.int-res.com/articles/meps_oa/m583p227.pdf

The researchers didn’t have a direct measure of the availability of sand-eels – they used proxies, including sea surface temperature, to estimate the local sand-eel population. They then concluded that sea surface temperature was the key issue.

There are additional issues. The Isle of May is located near the Scottish capital city Endinburgh in the mouth of the Firth of Forth, an estuary discharging several local rivers.

The Firth of Forth has seen several serious pollution scandals.

Back in 2007, a pump breakdown caused 170,000 tons of raw sewage to discharge into the estuary. The Firth of Forth also suffers substantial industrial pollution, including substantial levels of resinous plastics pre-cursors.

In 2014, Dalgety Bay on the shores of the Firth of Forth, just over the water from Edinburgh, was subject to a radiation scare – the beach was closed to the public, so it could be decontaminated by the Ministry of Defence.

I don’t know how much impact all this contamination has on the local wildlife. There is a lot of water in Firth of Forth estuary to dilute all that pollution. The radioactive contamination might have been mild – it doesn’t take much radiation to get bureaucrats excited.

On the other hand, the sea birds are at the top of a long food chain which stretches throughout the estuary. Apex predators and their immediate prey are often the most at risk of biomagnification of toxins through the food chain.

In my opinion, given the limited scope of the study – just one location – the indirect measurement of a key factor (population of sand eels), and the risk that other factors such as long term contamination with radioactive waste and other pollutants could have driven changes in diet, it seems premature to suggest climate change is the main culprit, without performing further studies in other hopefully less contaminated locations.

Update (EW) – Roy Mc provides evidence that sandeel fishing is the culprit, overfishing of sandeel is causing a decline in Scottish seabirds.

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123 thoughts on “Study: Warmer Water is Pressuring Scottish Shags

  1. So when the birds had easy prey, they ate that…..when they didn’t…they ate something else
    …bottom line…birds are doing fine

    2012 – 1982 = 30 years
    0.037 X 30 = 1.1 degree

    Sandeels must be incredibly delicate………

    • Latitude,
      They are nothing of the sort. In fact the smaller of the two British species (and probably the one eaten most by seabirds) often lives in intertidal zones. It MUST therefore be comfortable with wide temperature ranges.
      This so-called research is garbage. Shag populations and bait fish populations are well down on decades ago but there are a series of much better explanations for this (eg overfishing) than a temperature change statistically irrelevant to the equation.

      • ian, the closure of shortfall outlet sewage pipes since the early 80,s has been a major factor in the reduction of inshore biomass available as prey for many species.

      • Overfishing by humans seems very likely [from anecdotal pres cuttings].
        I would agree with Ian Magness, above: –
        ” . . . . the smaller of the two British species (and probably the one eaten most by seabirds) often lives in intertidal zones. It MUST therefore be comfortable with wide temperature ranges.”

        Auto
        PS – I guess
        Richard J. Howells, Sarah J. Burthe, Jon A. Green, Michael P. Harris, Mark A. Newell, Adam Butler,
        David G. Johns, Edward J. Carnell, Sarah Wanless, Francis Daunt – all ten of them – will get another grant.

      • Anti-science nonsense linked to the AGW funding teat.

        They should have looked at the amount of Commercial Fishing for Sand Eels – the Scottish ‘government’ highlighted this as a major problem in the decline of Sand Eels and in turn causing pressure on food supplies for Shags .

        http://www.gov.scot/Uploads/Documents/ME01ASandeels.pdf
        Sandeel fishing linked to Scottish Seabird decline :
        http://www.scotsman.com/news/environment/sandeel-fishing-linked-to-scottish-seabird-decline-1-3216052

        British Government Report on this :
        http://jncc.defra.gov.uk/page-5407

      • Just out of interest below is the email I have just sent to the ‘Centre for Ecology and Hydrology’ which led the study. They are based about 30 miles from me.

        Dear Dr. Fisher,

        I was very interested in this study and particularly to see no mention in the CEH article of the widely recorded and studied cause of the Decline in Sandeels (etc) in Scottish waters from Commercial Overfishing.

        Coincidentally this decline from overfishing is during the period that the study reports the decline of sandeels in Shag diets.

        The study attributes the decline in sandeels to ‘warming waters’ and I would be most interested to know what evidential study is relied upon to show that the studies suggested ~ 0.6 deg C warmer waters has directly caused the decline in Sandeel numbers as opposed to the known overfishing ?

        kind regards

        I included links to studies by the Scottish and Bitish Governments which firmly attribute the decline to commercial overfishing. I’m looking forwards to the response.

    • The birds are NOT doing fine… their breeding success has declined sharply around UK coasts due to the decline of sandeels. Which is down to warming seas.

      see for example:
      https://britishbirds.co.uk/wp-content/uploads/article_files/V95/V95_N03/V95_N03_P118_122_A005.pdf

      “In 2001, for example, the season was progressing well until the first chicks hatched, towards the second week of June. Suddenly, chicks began to die in the nest, and most Shetland colonies had failed completely by early July. Food shortage was undoubtedly the cause, in particular the lack of sandeels, which are the staple diet of Kittiwakes in Shetland during the summer, although the small local sandeel fishery, which is closely regulated to reduce its impact on breeding seabirds, cannot be blamed for this in recent years (see Brit. Birds 94: 151).”

      • Garbage. This was propaganda put about by the BBC and their green friends when breeding declined sharply between Aberdeen and Shetland. They blamed warming seas. The sandeels and birds that feed on them have been doing well in similar breeding grounds off the coast of wales where sea temperatures are much warmer than in the North of Scotland.

        The problem was massive over fishing on an industrial scale, mainly by Denmark. The Danes were supplying factories producing fish oil and Omega products for the healthcare market. The UK and EU have been trying to reduce the problem by introducing conservation areas.

      • The birds are NOT doing fine… their breeding success has declined sharply around UK coasts due to the decline of sandeels. Which is down to warming seas

        1.1 degree water temperature increase has stressed the birds? Such a specious statement is less than laughable. Even Barney Miller and Magnum PI would get a ‘tox’ screen to really see what’s going on.

      • “due to the decline of sandeels. Which is down to warming seas.”

        Griff, the paper you linked says colonies moved south…..if it was getting warmer, they would move north
        ….says the sand eel decline in the 1980’s “were followed by a resurgence in fortunes in the early 1990s,”
        says chicks are hatching before the sand eels hatch…says the sand eels are showing up later….which again would mean cooler water temps
        ..and says Great Skuas populations increased and learned to be predators of the Kikiwakes at the same time…1980’s….the decline started
        “”The predation of Kittiwake chicks
        and, at some colonies, adults and their eggs, and
        the increase in this behaviour during the past 15
        years, have undoubtedly been the major cause
        of the collapse of certain breeding stations””

        BTW….you’re talking about sea gulls….this post was about cormorants

      • Garbage. This was propaganda put about by the BBC and their green friends.

        And yet, you can count on Grift to parrot it.

      • Griff November 17, 2017 at 10:19 am
        The birds are NOT doing fine… their breeding success has declined sharply around UK coasts due to the decline of sandeels. Which is down to warming seas.

        So Sandeels are not being fished out of the sea then?
        http://www.telegraph.co.uk/news/uknews/1360127/Sand-eel-trawlers-sweeping-up-fish-stocks-in-N-Sea.html
        or
        http://news.bbc.co.uk/1/hi/scotland/3408113.stm
        “The Danish fleet, which dominates North Sea sandeel fishing, had a catch limit of nearly ONE MILLION TONNES last year but could only catch 300,000 tonnes.”

        The quota for Sandeels for 2017 has been ‘increased’, but not to 1,000,000 tonnes:
        http://www.fiskerforum.dk/en/news/b/best-sandeel-quotas-for-a-decade
        “The total Danish quota for sandeel is set at 458,000 tonnes for the three main sandeel areas in the EU sector of the North Sea and Skagerrak.”

        Of course this can be controlled with a Carbon Tax!

      • griff, over fishing and a hugely increased grey seal population competing for the same resource (the sandeels) are far better explanations than warming waters.

      • Griff November 17, 2017 at 10:19 am
        The same story is being played out in Antarctica where it is claimed Penguins are declining because of lack of Krill because of…climate change!. What are all those large factory ships doing hoovering up all the krill?
        https://www.theguardian.com/environment/2008/mar/23/fishing.food

        It seems there are those studying over fishing and those studying the climate and neither is talking to each other. It does seem very obvious that if you removes something (Sandeels, Krill) from a place (North Sea, Antarctica) then that something will no longer be in that place?

      • Um ! I thought you just said that the lack of sand eels is killing the chicks, but the local fishing of sand eels by humans is not to blame.

        How does a Scottish shag chick know that the sand eel it isn’t eating was caught by a local fisher(wo)man ??

        G

      • Food shortage was undoubtedly the cause, in particular the lack of sandeels, which are the staple diet of Kittiwakes in Shetland during the summer

        I see nothing but natural selection at work here. Plenty of species which are entirely too specialized, be it to a specific sandeel or budding flower, are at risk of extinction due to environmental factors wholly unrelated to what we as humans do or don’t do. Darwin himself assumed as much, that bottlenecks in adaptability puts certain species at much higher risk than those of others because they’ve co-evolved.

        Why should I feel guilt or sadness over something which is well beyond my control and happening with or without my influence? Over 95% of all species to have ever lived on the planet are now extinct; it’s entirely possible that kittiwakes are going to be just one more species to be added to the list of “Well, you really boned yourself there, mate.”

      • Griff – I suggest you look at the links I posted above to both British and Scottish Research findings that the Decline in Sandeels was a direct result of OVERFISHING – nothing whatsoever to do with climate.

        You should look a little wider than the AGW propagandist BBC – then you might see the facts rather than BBC fiction.

      • How can you prove the decline in shags was because of sand eels? I am sure you understand that proving things like this are what constitutes that little discipline we call “science”.

      • small local sandeel fishery, which is closely regulated
        ====
        any time a fishery is closely regulated you are guaranteed there is a problem with over fishing. warming is then used as a scapegoat for the failure of regulations to solve the effects of overfishing. this problem is nothing to due with climate.

      • As Ernest Lord Rutherford said: “If you have to do statistics, you should have done a better experiment. ”

        G

    • Ohhhhh … THOSE “Shags” …
      I thought they were claiming that Scots were shagging each other … more infrequently

    • pity the study ended in 2014. i spend a huge amount of time on the east coast of scotland fishing, there are a lot more sandeel on the forth banks this year than than at any point in the last 5 years . there has been a huge increase in the various north sea herring populations as well, with huge shoals of herring fry from the forth bridges to aberdeen and beyond all summer for the last few years.

      all marine based species are opportunist feeders, they need to be.marine creatures and fish rarely die of old age, it is a harsh environment. many have switched to the abundant herring fry ,so much so that the last two summer have seen the inshore cod populations become almost solely pelagic in their feeding habits ,only venturing to the bottom for prey like crab when the wind was onshore and the water coloured,this behaviour is usually associated with winter feeding patterns.

      there is a known issue relating to sandeel growth rate of the forth population, commercial fishing pressure in the past was on reason given for this. the other huge issue that no one seems to look at is the huge reduction in raw sewage along with fish and animal offal going into the inshore waters via shortfall sewage pipes and inshore dumping.

      as this has been reduced over the years since the early 80’s there has been a huge reduction in the biomass per square metre in the inshore area . from crabs and shrimps to the small fish like gobies and sea scorpions the numbers have decreased rapidly. one unintended consequence of “cleaning up” the water. another view taken by those that think humans are not part of nature as the waste products of all other life on earth end up in the oceans via river run off at some point.

      another point to make is the massive increase in the forth grey seal population (the uk in general has seen a huge increase ),so much so it appears the seal population survey information is no longer available(i think it would make too many people like ices look stupid). sandeel are a large part of north sea seals diet. as they now consume a greater weight of fish per year than are landed by the entire uk commercial fleet it might be worth a look by those studying the sandeel populations.

      this i feel has had a negative effect on plankton production and thus the available feeding opportunities for species like sandeel.

      as latitude says , no need to worry about the birds, they have plenty other sources of prey.

    • Year to year variations and seasonal variations are still higher and yet they survived for centuries. They survived for southern oscillation, circumpolar vortex related changes in temperature regime.

      Dr. S. Jeevananda Reddy
      .

      • I’ll pile into this comment thread portion since you’ve made superb remark regarding sandeel resilience to temperature, Dr. Reddy. Thanks!

        As a frequent fisherman, I’ve long known that sandeels are a preferred prey species for many fish; flounder, weakfish, sea robins, blowfish, etc..
        But, for the ordinary shore based fisherman, catching sandeels isn’t as easy as it sounds.
        Yes, sometime one can purchase frozen 1/4 kilo blocks of sandeels, but their body consistency is nearly mush then, and useless as bait.

        I took my two young sons to a state park with shallow sandy beaches near Chesapeake’s ocean outlet.

        While sitting in the shallow, and decidedly warmer water, trying to keep two young ones safe; I kept getting tickled where fundament met the sand.
        No matter how quickly I tried, I couldn’t catch the tickler. Which I assumed were sand fleas, also known as sand crabs, mole crabs, Ermerita) that dig through the sand.

        I got the kids to start trying to catch the sand fleas too; one drags their fingers through the sand and lifts them to the surface.

        We disturbed far more sandeels than sand fleas. When disturbed, the sandeels burst out of the sand, turn over and immediately wiggle back into the sand.

        I dislodged sandeels from right where waves lap the shore out to over six feet deep, where I dove under to rake the sand.

        Just in that fifty to seventy five yards of water, there was a substantial change in temperature from the bath tub warm sun baked water’s edge to the decidedly chilly deeper tidal flow.

        0.037°C per year, 1.1°C total difference over thirty years causes sandeel stocks to plummet?
        Howells et al demonstrates extreme confirmation bias and wastes a great deal of time and money pretending to conduct science. May the internet remember Howells’ falsehoods and embarrassment forever.

        Gross assumptions based on sham proxies.

      • Gabro November 17, 2017 at 4:24 pm
        “The North Sea was at least one degree C warmer during the Holocene Climatic Optimum than now…”
        And prior to this there was no North Sea for a good 50,000 years because sea level was much lower.

      • Stephen,

        Yup. Parts of it were still above sea level a scant 8000 years ago, around the Dogger Bank. Part of it was covered by ice during the LGM, as the British and Scandinavian Ice Sheet converged.

        So shags have survived much colder climate and enjoyed warmer.

    • Somebody needs to tell those Scottish shags, that trying to live on a panda diet of sand eels is a recipe for extinction.

      Eat something else you idiots !

      G

    • the statistical design of this paper has a fundamental mathematical error. they have used temperature as a proxy for food supply and from this concluded that temperature affects population.

      this paper never should have made it past peer review. in effect what they have discovered is that temperature = temperature.

      • let
        s = sandeels
        p = shags
        t = temp
        given
        p = f(s)
        assume
        s = g(t)
        then
        p = f(g(t))
        therefore
        p = h(t)
        in all cases, p is a function of t, not because of cause and effect, but rather because of the assumption that s = g(t)

    • “PS – I guess
      Richard J. Howells, Sarah J. Burthe, Jon A. Green, Michael P. Harris, Mark A. Newell, Adam Butler,
      David G. Johns, Edward J. Carnell, Sarah Wanless, Francis Daunt – all ten of them – will get another grant”

      Let’s hope so!

  2. “The North Sea is one of the most rapidly warming marine ecosystems on the planet, and warmed by 0.037 degrees Celsius per year between 1982 and 2012.”

    I don’t think a little more than a 1 degree rise in 30 years qualifies as significant enough climate change to cause the effects they say CC is responsible for. The 1 degree increase in ocean temps is not that significant within the natural seasonal variability so blaming the reduction or collapse of the Sandeel shouldn’t be blamed on a small amount of warming, natural otherwise. Other causes are likely a much larger candidate to explain this, and not mentioning anything else except a small increase in temperature kind of indicates a bias.

      • Well, there are cold water species like Antarctic krill and Bowhead whales. Certain foram species are used as warm and cold temperature proxies.

        But in general, yes, warmer is better for most aquatic species.

      • Actually most species would thrive better in colder water since the concentration of disolved oxygen is higher. Hence the seas around the poles are incredibly productive and the equatorial regions are comparatively barren.

    • Just how many total thermometers are there in the North Sea ?? I thought the number of thermometers in the arctic has decreased dramatically since the end of the Soviet Union era. I’ve read numbers as low as 12 for the entire Arctic.
      So don’t imagine I’m going to buy your 0.037 deg. C per year number.

      G

  3. Whatever caused it, in a more rational time, it would have recognized as a Darwinian response and written off. Now, there is an insane notion that NOTHING SHOULD EVER CHANGE. It fascinates me that evolution is taught as fact, then 100% ignored in climate science. Come one people, birds ADAPT. If humans are too foolish to do the same, then I suppose humans will be eliminated. Denial of change is generally fatal.

  4. I can assure Eric that sand eels in the region are not being affected by pollution and absolutely not by radioactivity.

    Seabird populations and their feeding habits at breeding sites in the vicinity have been studied in detail for decades.

    and so have the sandeels. Here is an extract from one such study:

    “The sandeel recruitment collapse observed in parts of the North Sea appears to be associated with warming seas and changes in zooplankton abundance and distribution. Zooplankton distributions are determined by oceanographic conditions such as sea temperature and the timing of stratification, with higher temperatures associated with northward shifts in Calanus finmarchicus. Sandeel recruitment is therefore likely to be reduced by warming seas, acting in part via zooplankton availability. “

    • And of course zooplankton populations are ONLY affected by sea temperatures… [facepalm]
      “Lets choose our favorite cause and then hunt for any correlation.”
      …bassackwards

    • Come on Griff!

      “The sandeel rcruitment collapse….”

      That MUST have been caused by Brexit, everything gets blamed on it!

      • The Sandeel Wars would be nolo contendre.

        Largest RDN surface combatant:

        Largest RN surface vessel:

        But Denmark could make more of a go of it than Iceland did during the Cod Wars. Despite its naval weakness, Iceland won however, when the UK agreed to a larger exclusive fishery zone in 1976. Iceland threatened to withdraw from NATO, complicating anti-submarine defense of the GIUK Gap.

    • Griff….here’s the paper you’re quoting
      http://roseatetern.org/uploads/3/5/8/0/35804201/workshop_report_tmh_v1_logo_pt.pdf

      quote this part too: “The proportion of sandeels in
      kittiwake diets has shown substantial year to year variation, but the decline over time is not
      statistically significant. “….so it don’t matter

      The blame warming water temps…and at the same time say bird nesting colonies are moving south, eels are hatching later, (( which means cooler water temps)), eel populations declined in the 1980’s which was cooler – and was followed by a resurgence in the 1990’s – which was warmer

      All of this points to ……… they don’t know what the hell they are talking about

    • Just like with any other previously unknown topic, some of us wait for Griff to chime in.
      He’s the perfect reverse barometer, always pointing away from the truth of things.
      Saves a lot of research time, actually. Griff approves? 97% certainty it’s BS.

      • I honestly think Griff reads something until he sees what he wants….like “warming”….and stops reading or thinking at that moment….and most of the time makes a total fool of himself because of that

    • Yep, “appears to be”. Very scientific.
      Amazing what an increase of 0.037 degrees Celsius can do.
      “The North Sea is one of the most rapidly warming marine ecosystems on the planet, and warmed by 0.037 degrees Celsius per year between 1982 and 2012.”
      But that must be good news for everywhere else because their seas have warmed by less than 0.037 degrees Celsius.
      However tourism to places like Skegness and Scarborough must be booming as a result of all that warming of the North Sea. No doubt the relevant universities need extra research funds to study the impact of mass tourism on these places.

      [0.037 total, or 0.037 per year? .mod]

    • bollocks griff. explain the recent increases in north sea cod numbers if that is the case. calanus finmarchicus is the main plankton species required for good recruitment of the gadoid species in the north sea. numbers of c.finmarchicus in the north sea were in decline, i suspect they are now on the increase though i cannot get access to the data from the continuous plankton recorder to check.

  5. From the article: “Such changes may alter interactions with potential threats, such as small-scale offshore renewable developments.”

    I guess they consider off-shore renewable developments (windmills) to be potential threats. Doesn’t this disparaging of windmills disqualify the authors from getting any Climate grant money? They will probably have to give the money back.

  6. One thing I am sure of is that the warming, if any, of the atmospheredoes not affect the temperature of the ocean. It just can’t The heat capacity of the ocean is 1000 times that of the atmosphere. In which direction do you think the arrow points.

  7. As a Scientist trained in Scotland, I am ashamed that this sort of “science” is tolerated in my country.

  8. Sometimes when I’m scanning the articles here,
    I get confused and think I have accidentally logged into
    the comic website: The Onion.

    It seems as if the global warmunists
    are having a competition to see who can write the most bizarre scary story
    they can attribute to “climate change”.

    I just want to know who pays for all these useless “studies”?

  9. Anything that sort of, kind of, possibly even hints at “climate change” must be “climate change.” There’s no other explanation!

    Sheesh!

  10. Sitting here in Dalgety Bay overlooking the Forth, it is now too dark to see the shags fishing.
    The decline in seabirds in the North Sea, including shags, is well attributed to industrial scale fishing of sandeels. http://www.scotsman.com/news/environment/sandeel-fishing-linked-to-scottish-seabird-decline-1-3216052
    The radiation consists of a few particles of radium. These come from luminous paint used on instruments of WW2 aircraft which were broken up and buried at Donbristle airfield and which are now being exposed by coastal erosion. This has resulted in a short section of foreshore being closed as a precautionary measure, and a project to remove material and seal the area with rock armour due to start in the Spring.
    It is possible that a shag or two may have ingested a radioactive particle, but that would not have a population effect.
    The Forth has been heavily industrialised for centuries, for example with the world’s first under sea mine, the Moat Pit being opened in 1595. It is now cleaner than it has been for centuries, so wildlife decline due to pollution is not a tenable explanation.

    • Thanks Roy. So we have:

      a) Small hardly detectable sea water temperature shifts?
      b) Centuries long industrial pollution now in decline?
      c) Massive over-fishing resulting in substantial reduction of this seabird’s staple diet?

      Which of these is likely to have reduced shag numbers?

      Answers on a postcard.

    • Seems as if sandeels are popular not just with human fishers but a variety of birds. Shags have a lot of competition:

      Indetectably warmer water is the least of their concerns.

      • gabro, if you want to see that image in real life head to the cliffs south of aberdeen in summer time. the headland half a mile south of portlethen sees numerous puffins feeding on sandeel. i am constantly amazed at how many sandeel one puffin can get in its beak on one dive. incredible to see and just one of the many joys of being a sea angler on the scottish coast.

      • Thanks for your ground truth comments. Or sea truth.

        That is indeed a neat trick which puffins can do with their beaks.

        I was in Aberdeen in the summer of 1974. Was still light at ten PM. Took advantage of no trespass camping. Turned out on the B roads to let the sheep pass. But unfortunately didn’t go sea fishing.

        Lots of tufted puffins on the Oregon coast, but they tend to hang out on offshore islands and sea stacks rather than the shore.

  11. “…it seems premature to suggest climate change is the main culprit, without performing further studies in other hopefully less contaminated locations.”

    Fishing for a grant? /sarc

  12. One way to rule out environmental contamination would have been to test the birds and their stomach contents. But I guess these folks were too busy coming up with some other way to determine the number of eels without having to actually count them to think of something as straightforward as that.

    • So we should kill more Scottish shags to open their stomachs to find out what is killing them !

      Just another facet of the problem of university biology department store rooms full of drawers filled with dead specimens of now extinct species of critters.

      G

  13. With proxy data like this, such a confidently expressed conclusion is “conflict-of-interest” nonsense. This corrupted fraternity (although anyone following my comments recently will note climate science is becoming a sorority) strains beyond limit negative effects of warming (which itself may be cooked – everybody in the game quickly adopted the egregious Pause busting Karlization of SST temperatures on June 2015, days before his (Karl) retirement). I say conflict of interest because these warriors would go on half baked data, but would be mum if they came across good news data.

    Finally, I’m sure these birds are more eclectic eaters than advertised.If not, then they will simply become Swedish shags! As a mining and metallurgical engineer, Im becoming an advisor here on the biosphere, atmosphere, hydrosphere as well as my formerly narrower lithosphere specialty. Vacancies in these new areas abound!

  14. Put this in the ‘unadulterated propaganda, because surely they can’t be that stupid department.’

    Did no one bother studying these birds prior to 1985? Were they all busy measuring the ozone layer over Antarctica instead? No, there is a survey from 1969-70 that apparently was just too inconvenient for the propag…err study.

    http://jncc.defra.gov.uk/page-2877
    Operation Seafarer
    (1969-70) 29,956
    Seabird Colony Register
    (1985-88) 36,276
    Seabird 2000
    (1998-2002) 26,565

    Looks like this bird has a cyclical population controlled by its predator/prey relationship with the sand eel to me. But then again, it’s 10 degrees warmer today than yesterday, so we could all cook to death by this time next week.

  15. I think some offshore wind turbines will be the most humane way to resolve this problem by putting the birds out of their misery quicker. Death by starvation is so cruel when one can euthanise these birds more efficiently with AGW solutions.

    [Your pithy satire is noted and appreciated, but the mods respectfully request that you pick a single username and stick with it. Thank you in advance for your cooperation on this issue. -mod]

  16. I cannot see any evidence in the study that the change of diet is damaging the shags; it is just the usual knee jerk “change bad.”

    Perhaps the change is because other species of prey have move into the area, benefiting from all the warmth, and the shags are taking advantage of this.

    I see it does mention “potential threats, such as small-scale offshore renewable developments.” i.e. wind farms are the big killer.

  17. I had no idea what the common name for that species of what looks like a cormorant was. It is really convenient for headlines, though.

  18. Hug a windmill or solar panel wiring assembly if the cold opposite occurs. They and you will need something in the coming cold cycle of the AMO with overlay help from extended solar cycle low and ENSO. Just don’t expect total deforestation of North America for your wood pellet import business.

  19. Just for the record, is that a pressured or unpressured Scottish Shag (Phalacrocorax aristotelis). in the lead photo? It could be important for us to know. He looks quite happy in either event.

  20. Like all cormorants, shags’ diet is diverse. They’ll eat just about any fish they can catch. Where present, they even eat sea snakes. Like sea lions, human fishers don’t like their competition.

    • In fact, cormorants evolved from inland birds, so can even feed in freshwater if need be.

      Chinese and Japanese fishermen use them in lakes.

  21. In recent years, off the South West tip of Scotland in Galloway, for example, inshore declines of sand eels have had nothing to do with virtually imperceptible changes in water temperature. The most significant impacts have been caused by a combination of aggressive trawling in feeding grounds and silt run off from local rivers in a succession of spate years contaminating the same inshore areas. This, in turn, has led to increased numbers of inshore eel feeding birds, such as cormorants on the west coast, being driven inland and devastating nearby fisheries, lochs and rivers. In the long term, a few very wet years close together are nothing unusual in the local precipitation record. It’s called ‘natural variation’. The eels just move off to more hospitable environs elsewhere out of reach of the inshore bird populations that normally predate them. The actions of trawler skippers might be deemed ‘unnatural variation’. The problem may be partially man made but, sorry Griff, you can’t pin this ‘shaggy dog story’ on global warming.

    • As if shags are the least bit endangered, anyway. They’re rated as “Least Concerned” in conservation status in the IUCN Red List. Their range is large, breeding in western and southern Europe, southwest Asia and north Africa. Its fellow member of the same genus, the great black cormorant, is distributed even more widely. Their ranges overlap:

  22. I have often enjoyed Griff’s contributions, sometimes interesting or provocative, and sometimes on aspects of the “it’s because of our carbon dioxide emissions/global warming” subjects about which I don’t know enough to comment. I usually read his comments and the responses to see how the arguments are being made. This latest thread has however fatally damaged his credibility in my eyes. He seems to have ideological blinkers on.
    Three generations of my paternal family were herring fishermen. Of the next lot, my uncle was a skipper on a white fish trawler (and subsequently was the ‘fishing’ skipper on a fisheries research vessel), and my father was meteorologist, sometimes on weather-ships. There isn’t much I haven’t been told about fishing in Scottish waters.
    Herring were over-fished even in the days of the drifters, although the collapse of the Baltic trade for salted herring after revolution and wars assisted in the decline of the industry. Fast-forward to the 1970s and the tottering UK government, in an attempt to garner votes, made its idiotic protest about Iceland’s perfectly sensible 200-mile foreign fishing boat exclusion zone due to the marginal Labour seats in Hull and Grimsby, home ports for the major English deep-sea fleets. We should have instead said “What a jolly good idea, let’s do the same”. But having done what we did, as a member of the EU, it was quotas all round for foreign boats, and the decline of the UK industry accelerated. UK fishermen couldn’t catch herring for people to eat, and seine net boats from Denmark were scooping out herring to feed to pigs, and the bacon was then being sold in the UK. UK pig farmers and fishermen were going out of business at the same time. Marvellous, and the UK herring fishery collapsed. I can remember standing on the pier in Lerwick watching the boats and being astonished at the tiny mesh on the nets.
    Subsequently, with a non-food demand for oily fish and the herring wiped out, the sand-eel fishery took off, again with the Danes getting big quotas, and you don’t have to be a genius to work out why bird and larger fish species that eat sand-eels are in decline when the fishermen granted the quotas can’t actually achieve them.
    Throughout all this, the sclerosis in the EU fisheries management has been painful to watch. Boats throwing already dead fish overboard (discards) as to land them would have violated their quotas, is just immoral. It’s taken decades to establish conservation no-fish zones, and have regulations about mesh designs and sizes brought in, with Scottish fishermen and researchers often leading the way and the EU dragging its heels.
    No Griff, neither you nor the authors of misguided papers can blame “climate change”, however “on-message” that might be . As well as natural periodic variations, sand-eels are in short supply because they’re being scooped out of the sea too fast. Better to leave them there for the sea-birds and bigger (tasty) fish to eat. The only anthropogenic factor hammering sand-eel populations in UK waters is the ruddy EU fisheries management policies.

  23. The common cormorant or shag
    lays its eggs in a paper bag.
    The common Gallinule or Rail
    Lays its eggs in a plastic pail.

    (crickets)

    • Thanks, was trying to rember the two opening lines. The rest show that shags may be the climate scientists of the avian world.

      ‘You follow the idea, no doubt?
      It’s to keep the lightning out.

      But what these unobservant birds
      Have never thought of, is that herds
      Of wandering bears might come with buns
      And steal the bags to hold the crumbs.’

      Christopher Isherwood (which reminds us that ‘Money Makes The World Go Round’)

  24. I used to holiday with my family on the east coast in the 70s/80s and when they started fishing for sand eels to use for agricultural fertiliser the numbers dropped like a stone and so did the number of others that fed on them.

    • Fishing for fertilser used to happen accidentally. In the 1920s My grandfather failed to sell one catch of herring at the market in Lowestoft (the traditional winter season when the scottish herring fleet would go south). A local farmer bought the lot and spread the unprocessed herring on his fields. The greedy gulls would come and gorge themselves to the point where they couldn’t fly, then waddle around depositing their guano.

  25. I have often enjoyed Griff’s contributions, sometimes interesting or provocative, and sometimes on aspects of the “it’s because of our carbon dioxide emissions/global warming” subjects about which I don’t know enough to comment. I usually read his comments and the responses to see how the arguments are being made. This latest thread has however fatally damaged his credibility in my eyes. He seems to have ideological blinkers on.
    Three generations of my paternal family were herring fishermen. Of the next lot, my uncle was a skipper on a white fish trawler (and subsequently was the ‘fishing’ skipper on a fisheries research vessel), and my father was meteorologist, sometimes on weather-ships. There isn’t much I haven’t been told about fishing in Scottish waters.
    Herring were over-fished even in the days of the drifters, although the collapse of the Baltic trade for salted herring after revolution and wars assisted in the decline of the industry. Fast-forward to the 1970s and the tottering UK government, in an attempt to garner votes, made its idiotic protest about Iceland’s perfectly sensible 200-mile foreign fishing boat exclusion zone due to the marginal Labour seats in Hull and Grimsby, home ports for the major English deep-sea fleets. We should have instead said “What a jolly good idea, let’s do the same”. But having done what we did, as a member of the EU, it was quotas all round for foreign boats, and the decline of the UK industry accelerated. UK fishermen couldn’t catch herring for people to eat, and seine net boats from Denmark were scooping out herring to feed to pigs, and the bacon was then being sold in the UK. UK pig farmers and fishermen were going out of business at the same time. Marvellous, and the UK herring fishery collapsed. I can remember standing on the pier in Lerwick watching the boats and being astonished at the tiny mesh on the nets.
    Subsequently, with a non-food demand for oily fish and the herring wiped out, the sand-eel fishery took off, again with the Danes getting big quotas, and you don’t have to be a genius to work out why bird and larger fish species that eat sand-eels are in decline when the fishermen granted the sand-eel quotas can’t actually achieve them.
    Throughout all this, the sclerosis in the EU fisheries management has been painful to watch. Boats throwing already dead fish overboard (discards) as to land them would have violated their quotas is just immoral. It’s taken decades to establish conservation no-fish zones, and have regulations about mesh designs and sizes brought in, with Scottish fishermen and researchers often leading the way and the EU dragging its heels.
    No Griff, neither you nor the authors of misguided papers can blame “climate change”, however on-message that might be . As well as natural periodic variations, sand-eels are in short supply because they’re being scooped out of the sea far too fast. Better to leave them there for the sea-birds and bigger (tasty) fish to eat. The only anthropogenic factor hammering sand-eel populations in UK waters is the ruddy EU fisheries management policies. Take your blinkers off Griff, you’ll find you can see a lot more.

    • Let’s hope you’re right SR and UK does not give them away in another pathetic attempt to curry favo(u)r with EU. May seems to be doing her best to mess things up and she has form.

  26. This is what the Scottish Government has to say about Sand Eel populations and fishing.

    Managing Sandeel Stocks
    The International Council for the Exploration of the Sea (ICES) recommends that local depletion of sandeel aggregations by fisheries should be prevented, particularly in areas where predators congregate. In the light of studies linking low sandeel availability to poor breeding success of kittiwake, ICES advised a closure of the sandeel fisheries east of Scotland for 2000-2003. All commercial fishing was excluded, except for a maximum of 10 boat days in each of May and June for stock monitoring purposes. The closed area is being maintained for three years with an evaluation every year. Marine Scotland Science is involved in providing the advice for this evaluation. Furthermore there are a number of ongoing empirical and modelling investigations of sandeels and interactions between sandeels, predators and the fishery.

    Stock management currently treats sandeels in the North Sea as a single population. However, research co-ordinated by Marine Scotland Science indicates that there are a number of stock components in the North Sea which, because of isolation of suitable habitat and limited larval movements, do not inter-mix. Given the potential for differences in growth, recruitment and mortality between these stock components, the present management of the stock by a single Total Allowable Catch (TAC) covering the whole North Sea makes sandeels vulnerable to regional over-exploitation. Scientists from the UK and Denmark are now trying to understand the dynamics of regional stock components in order to provide advice on regional management.

    It seems the North Sea Sand Eel population is vulnerable to over fishing. In contrast the Shetland Sand Eel fisheries have been controlled since the late 1980s because of the damage being done to other predators, Puffins in particular if my memory is correct. Minor changes in water temperature seem to be less of a problem than over fishing.

  27. hmmm. Several studies have confirmed that oceanic flora and fauna, just like land flora and fauna, follow decadal oceanic oscillations. I am willing to bet that some of this shad downturn could be related to a natural decadal migration pattern. The only reason why the Padific salmon pattern was identified was because of fishing vessal logs from way back demonstrating such a pattern.

  28. using temperature as a proxy for food supply and then concluding temperature affects population is mathematical nonsense. this. paper should have been rejected for a fundamental mathematical error in experimental design.

  29. Late to this discussion, but comments above are very interesting, with those from SONOFAMETMAN’S worth reading twice. Here is an older paper showing a population explosion from reduction of herring and mackerel populations. (Sherman, K., C. Jones, L. Sullivan, W. Smith, P. Berrien and L. Ejsymont. 1981. Congruent shifts in sand eel abundance in western and eastern North Atlantic ecosystems. Nature. 291:486-489). I also seem to remember an older U.S. paper about shifts with temperature. In the Gulf of Mexico cormorants compete more with fish than with other birds, except for the few loons, grebes and mergansers in winter, and others in crawfish ponds. I get in trouble with friends of birds by kidding them about bringing back the feather industry to save them and fish, but some lack a sense of humor. I read about his run in about lack of humor in one of Roy Spencer’s book so I am in good company.

    This was in Ireland, but food must be important.
    Tománková, I., C. Harrod, A. D. Fox and N. Reid. 2013. Chlorophyll-a concentrations and macroinvertebrate declines coincide with the collapse of overwintering diving duck populations in a large eutrophic lake. Freshwater Biology. doi.10.1111/fwb.12261. The ducks ended up in a more northern climate, so warming was also invoked, but Gulf of Mexico ducks go north every summer.

    While the paper was not studied adequately, it lacks the Sherman, et al., paper, but they know about Ashmole’s halo: direct evidence for prey depletion by a seabird. However, this caveat (among others) sounds important—“We selected C. finmarchicus abundance as a proxy of egg production, since eggs and nauplii of this species are key prey of younger age classes of sandeel (van Deurs et al. 2009). Thus, there are multiple intermediate steps connecting C. finmarchicus and sandeel abundance that may each serve to weaken the relationship between them. ”

    This is also an interesting book on the subject.
    Hall, S. T. 1999. The Effects of Fishing on Marine Ecosystems and Communities. Blackwell Science, Oxford. 274p.

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