Marsh Harriers (1 Viewer)

Karl J

Well-known member

• Feb 15, 2004

• #1

Observing Marsh Harriers in various parts of Norfolk this last little while (few months i guess) I've seen very few males, do they migrate south and leave mainly females behind ?

I guess it's possible, though thinking about it I don't think it's the case with the regular local patch birds at least, that it's mistaken id - young juvenile (or sub-adult or whatever the correct term is) with their female-like plumage for true female. Thinking about this had led to another question, if anyone knows ....

How long does it take a chick to achieve full adult male plumage ?

Personally I find them fascinating to watch, as they glide slowly over the marshes looking for the next meal & consider it one of the major bonuses of my local patch as they're here all year.

Thanks in advance

 

Adey Baker

Member

• Feb 15, 2004

• #2

2 points:

Yes, young birds of several harrier species are similar to adult females and more importantly, male Harriers are polygamous - hence more females!

Adey

 

pauco

Старлин&

• Feb 15, 2004

• #3

Carlos, have you seen the interchange of food, as the male arriving with food, calls the female from the nest. she rises from the nest and flies to meet him, he may then drop the food with her flying below him and catches with a lovely twist in mid air, or she flies up to meet him, turns over and receives the food by foot to foot pass. The only way to describe this beautifully timed movement is
WOOOOW. I hope you get the chance to see it.
bert.

 

intellectual

Well-known member

• Feb 15, 2004

• #4

Living in north Lincs, I'm privileged to see one of my favourite birds the Marsh harrier. They nest at two local reserves. Blacktoft Sands is one of the best palces round here to view them. Last year got close views of them while in the hides, such a magnificent bird.
Also saw three juveniles last year or year before at the other local reserve, flying alone, but I daresay the parents were keeping a close watch.
Intellectual

 

Karl J

Well-known member

• Feb 15, 2004

• #5

That ties in quite nicely with what i saw last year Adey, but recently I was at a roost & there had to be 10 females to 2 males ... thats 5 each !! .... can they really that keep that many on the go ?

Any idea how long it takes for a male to reach that full adult plumage ?

 

A

alcedo.atthis

Well-known member

• Feb 15, 2004

• #6

Age of adult plumage

Any idea how long it takes for a male to reach that full adult plumage.

Carlos, adult plumage reached in completion of moult, October, (November) prior to 4th Winter.

Regards

Malky @ Westhill

 

Karl J

Well-known member

• Feb 15, 2004

• #7

Just prior to 4 th winter ... that long eh ... I had no idea it was so long.

Sounds a reasonable guess then that some of the 'females' i've seen have indeed been younger birds.

Interesting

 

A

alcedo.atthis

Well-known member

• Feb 15, 2004

• #8

Ageing Marsh Harriers

> Just prior to 4 th winter ... that long eh ... I had no idea it was so long.

> Sounds a reasonable guess then that some of the 'females' i've seen have indeed been younger birds.

> Interesting

Carlos, if you get the chance to read Dick Forsman's book on the Raptors of Europe and the Middle East, it's worth the learning from. Extracted from said,
"Adult male, (from 3rd Calander year autumn and older)"

"Adult males may further be devided into, 'younger adults' (probably from 3rd cy autumn to 4th/5th cy summer) and 'old adults' (at least in their 6th cy), but since the individual variation is not yet fully understood these types are better referred to as plumage-types, rather than exact ages."

Females turn adult in 3rd calander year summer when moulting, *as the males)

Tha above would basically agree with the ringers guide relative to ageing.
Hope that this clarifies

Regards

Malky @ Westhill

 

Karl J

Well-known member

• Feb 15, 2004

• #9

Yes many thanks Malky.. I've seen references to this book in other threads .... i'll see if i can get into the library this week sometime & order that.

 

Jamspangle

Up the boro!

• Feb 20, 2004

• #10

Carlos GY said:

Observing Marsh Harriers in various parts of Norfolk this last little while (few months i guess) I've seen very few males, do they migrate south and leave mainly females behind ?

Click to expand...

I have wondered about this myself as on the Delta in winter we get lots of Marshies (record being 14 in a loose group near tancada - a local lake) and i would say 19 out of 20 we see are females/juvs. Where do all the males go or is it just that not many males reach full adulthood?

 

Karl J

Well-known member

• Feb 20, 2004

• #11

Hi Jamspangle, got Dick Forsmans book from the library today but haven't had time to look at it yet. It does appear to be quite a comprehensive book so maybe it'll shed some light on it.

I was wondering if the males migrate further south, but if the book turns anything interesting up I'll post it up here.