Bird of the day

3lbgrayling

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Was reading-up on ferox for the ongoing brownie thread and spotted an interesting piece...

Said that while nesting black-throated divers tend to feed on freshwater fish, red-throated divers, though they breed on freshwater, tend to fly off to the sea to feed, thus bringing biomass back from the sea to nutrient-poorer freshwater habitats. Same idea as salmon feeding at sea and then dying after spawning and bequeathing their body mass to the spot their offspring need the nutrients from to start the next generation.

Not sure if there is anything in it for the R-TDs? Maybe their chicks start to feed on freshwater fish before migrating away?

Anyhoo - big-up the R-TD! (y)

Good excuse to keep things ticking over by digging into the back catalogue for pics of red-throated divers... 😜

Loch Fada, South Uist...





Loch of Harray, Orkney...











Col

whilst fishing on the wee G for 19 years. you would hear the RTD high in the sky heading down to the bay.to fish.and sometimes hear them heading back.to sometimes very small lochs/puddles. rather than the giant Fionn loch..I always took a Scope with me to the lodge and you could have up to 20 RTD fishing in the bay.

Jim
 

bobmiddlepoint

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Was reading-up on ferox for the ongoing brownie thread and spotted an interesting piece...

Said that while nesting black-throated divers tend to feed on freshwater fish, red-throated divers, though they breed on freshwater, tend to fly off to the sea to feed, thus bringing biomass back from the sea to nutrient-poorer freshwater habitats. Same idea as salmon feeding at sea and then dying after spawning and bequeathing their body mass to the spot their offspring need the nutrients from to start the next generation.

Not sure if there is anything in it for the R-TDs? Maybe their chicks start to feed on freshwater fish before migrating away?

Anyhoo - big-up the R-TD! (y)

Col

When I lived on Uist our house was right on the shores of a sea loch and on the flight path of three or four pairs of RTD as they went to and from nest to sea feeding. Preferred diet appeared to be small pollack (of which there are millions around Uist) in the 3 - 6 inch range. One slightly unusual thing about RTDs is that they carry fish home to the nest sideways rather than pointing forwards. This looks very un-aerodynamic but then I suppose puffins do the same with sandeels. It does make it very easy to ID the prey.

FWIW almost all the RTD nesting lochans on Uist were fishless bog pools so the young weren't getting any food from them. I think they choose these type of lochans for nesting as the water level is very stable and tends not to go up and down very much in summer. They like to nest right on the edge about 2" above water level so a burn fed loch would see them flooded out in most Uist summers. Funnily enough about the only RTD nesting loch on Uist that didn't fit this pattern was Fada. Even in Fada with a good head of small trout/sea trout the adults always went over to the Atlantic coast to feed. I can't think I ever saw a RTD fishing in freshwater on Uist.


Andy
 

3lbgrayling

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When I lived on Uist our house was right on the shores of a sea loch and on the flight path of three or four pairs of RTD as they went to and from nest to sea feeding. Preferred diet appeared to be small pollack (of which there are millions around Uist) in the 3 - 6 inch range. One slightly unusual thing about RTDs is that they carry fish home to the nest sideways rather than pointing forwards. This looks very un-aerodynamic but then I suppose puffins do the same with sandeels. It does make it very easy to ID the prey.

FWIW almost all the RTD nesting lochans on Uist were fishless bog pools so the young weren't getting any food from them. I think they choose these type of lochans for nesting as the water level is very stable and tends not to go up and down very much in summer. They like to nest right on the edge about 2" above water level so a burn fed loch would see them flooded out in most Uist summers. Funnily enough about the only RTD nesting loch on Uist that didn't fit this pattern was Fada. Even in Fada with a good head of small trout/sea trout the adults always went over to the Atlantic coast to feed. I can't think I ever saw a RTD fishing in freshwater on Uist.


Andy

I agree with you on this Andy.

Jim
 

Cap'n Fishy

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When I lived on Uist our house was right on the shores of a sea loch and on the flight path of three or four pairs of RTD as they went to and from nest to sea feeding. Preferred diet appeared to be small pollack (of which there are millions around Uist) in the 3 - 6 inch range. One slightly unusual thing about RTDs is that they carry fish home to the nest sideways rather than pointing forwards. This looks very un-aerodynamic but then I suppose puffins do the same with sandeels. It does make it very easy to ID the prey.

FWIW almost all the RTD nesting lochans on Uist were fishless bog pools so the young weren't getting any food from them. I think they choose these type of lochans for nesting as the water level is very stable and tends not to go up and down very much in summer. They like to nest right on the edge about 2" above water level so a burn fed loch would see them flooded out in most Uist summers. Funnily enough about the only RTD nesting loch on Uist that didn't fit this pattern was Fada. Even in Fada with a good head of small trout/sea trout the adults always went over to the Atlantic coast to feed. I can't think I ever saw a RTD fishing in freshwater on Uist.


Andy

I wonder what the ones we see on Harray are up to then, if they feed on sea fish? :unsure: You see single birds spending quite a bit of time on the loch, well away from wherever their nest and/or chick might be. You see them diving, though it's possible that is just to make themselves scarce, as there are people in boats in the vicinity?

I don't know if the RSPB types put out nesting platforms for R-TDs. We see one or two of the ones they put out for B-TDs, on lochs. They do the same thing of nesting right at the water's edge (coz they can't really walk), but a floating platform just rises up in times of flood and keeps the egg dry. Seems to work well. This pair use a platform...



Col
 

codyarrow

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Feb 6, 2010
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It could be me but the lack of shooting is having an effect on the geese and grouse. The grouse are cackling in places they would not normally be and are showing themselves more. The geese flying into the loch on an evening all seem to be flying a lot lower than a normal year.
Not one shooting party this year.
 

easker1

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the RTD's here have a boggy stank but I see them often on the sea as well as GND's I hear them most days during the summer, easker1
 
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