Latvian Osprey nest 2019-2023

[Owlie]

Teo is mantling

both flew away

I don't see anyone in the nest 12:19

[Liz01]

12:20 Teo is back. He crop is empty So he gave the fish to the Lady ?

I don't see anyone in the nest 12:19

Owlie, there is no timestamp! I was taking pictures and wasn't sure if it was still 10:59 when they flew away

[Liz01]

There were three birds.. Teo & the female and another Osprey or WTE

She sees someone in the sky.. alarm calls and both flew away

[Owlie]

19:09:30 a goshawk flew in and chased Teo away - coming from under the nest rim in this bad picture, in the middle

[Liz01]

19:09:30 a goshawk flew in and chased Teo away - coming from under the nest rim in this bad picture, in the middle

Owlie well spotted

I will do a SLOMO video


Teo is doing well! He was flying on the left. Goshawk was not visible. The attack was unsuccessful
It only works if he can overwhelm the victim. Teo saw him in time

[Liz01]

Attack is speed 0,1! thereafter Teo is calling and is flying on the right

[asteria]

It would be better if Teo and his new partner would have found another place for nesting. They have no chance to grow the chicks. Goshawks won't leave them in peace.

[Liz01]

April 11


good morning

6:04 Teo landed on the camera

[Floppy Fish]

Around 13:52:12 there was another hawk visit. Possibly the same one that tried to attack Teo yesterday. I think that was a sparrowhawk in both cases.

On this snapshot of yesterday's attacking hawk, the small beak, thin legs and the long middle toe tell me this is a sparrowhawk.


For today's visiting hawk, I made a composite image for comparison, all of them taken at this nest this year and last year:

Legend:
A: Teo at 2021-04-10 10:59:27
B: Unringed female osprey at 2021-04-10 10:59:27
C: Hawk, sighted at 2021-04-11 13:52:12
D: Goshawk, sighted at 2020-06-30 17:28:25
E: Juvenile sparrowhawk, sighted at 2020-07-18 17:23:39
F: Comparison of beaks between today's hawk and goshawk
G: Long middle toe on visiting hawk

Judging by size, one could think today's hawk (C) might be a smaller male goshawk, but comparison of the beaks (F) of the goshawk (D) is much longer and eagle-like. Today's hawk (C) also has thin legs, similar to the juvenile's legs (E), and the distinctive long middle toe (G)

They seem convinced it was a goshawk in Latvia at the moment, but I disagree. I will try to translate it so I can repost it in the Latvian forums.

[Liz01]

Floppy fish, that is a goshawk!
A sparrowhawk would have absolutely no chance against an osprey

Female sparrowhawks are about the same size as the common kestrel, males about 1/3 smaller.
Female goshawks are about the size of a buzzard, Males are only about 25% larger than female sparrowhawks (but twice to four times as heavy!) And can therefore not always be immediately distinguished based on their size.

[Floppy Fish]

Floppy fish, that is a goshawk!
A sparrowhawk would have absolutely no chance against an osprey

I don't think this hawk calculated its attack plan thoroughly before it swooped at the nest... From what I have seen, hawks usually approach a nest from below before having a good look at what is awaiting inside. If there is a bird larger and fiercer than them inside, it can end up fatally for the attacker. The hawk definitely did not press the attack; it probably changed its mind once it saw up close how large Teo was.

Female sparrowhawks are about the same size as the common kestrel, males about 1/3 smaller.
Female goshawks are about the size of a buzzard, Males are only about 25% larger than female sparrowhawks (but twice to four times as heavy!) And can therefore not always be immediately distinguished based on their size.

Goshawks and sparrowhawks come in various sizes, and I agree that size just by itself is not a reliable way to tell male goshawks from female sparrowhawks.

The beak and the legs on the other hand, are a much more accurate way to tell them apart. You can see that the legs of today's hawk are identical to the juvenile sparrowhawk's legs despite its body size. You can also see that the beak is much smaller than a goshawk that visited the nest last year.

I think the large body size could be explained by it possibly being a sparrowhawk from up north being on migration. I looked up the timeline for migration, which shows ~50% of Finnish sparrowhawks arriving between March 15 and May 1, while ~95% of them arrive between March 15 and June 1. (source, figure 1)

I also looked up whether Bergmann's rule (bigger body size up north) applies to sparrowhawks, it seems that it does apply:

A marked latitudinal trend in the body-size of Sparrowhawks was found within Britain, with birds of each sex and age group increasing in size from south to north, in line with Bergmann's Rule. For each successive degree of latitude (approximately 110 km), wing-length increased by an average of 0.86 mm in adult males and O.75 mm in adult females.

Source: https://www.researchgate.net/publicatio ... in_Britain

[Florinda]

Around 13:52:12 there was another hawk visit.

[Liz01]

Florinda, thanks for the pictures! I still wait of my download.

Floppy Fish,
I don't argue about Sparrowhawk or Goshawk. You won't be able to prove it was a Sparrowhawk.
For me the pictures and the size, it's a goshawk.

The way of hunting is different! They come from above, from the side or from below. always as it is convenient for them. Believe me, I've videoed countless attacks.

Black Storks, Ospreys and so on...

[handbyl]

Osprey nests are so open to the sky - or at least those I have seen are so.

Kind of inviting the attention of bird catching raptors as we well know from 2020

[Liz01]

feather colors Goshawk
https://www.featherbase.info/de/species ... r/gentilis

feather colors Sparrowhawk
https://www.featherbase.info/de/species/accipiter/nisus

13:52:11




visit Speed 0,2

[Polly]

April 12th

There are dangers for all of our animals everywhere and at all times.
Maybe it's 'good' that events happen so early in the season. It is up to Teo whether he feels threatened and withdraws or stays.
We can only watch.
Teo is certainly aware of the danger. I don't know if animals can 'forget' ... but this nest has been robbed in many other seasons as well. Nevertheless he stays. I have no idea if animals can think strategically or if they just act instinctively (for example, breed).

I still hope for a good turn.

Currently the nest looks like a palace and a new pretty lady has arrived. Matches the nest with a gold ring. (JNH)

[Polly]

Teo manages what is not firmly on the ground.







Hm, no sign of Vita so far ...

[Polly]

And further ...

[Polly]

let's go

Out with empty claws ...


And back ...


Okay, Teo is planning a protective wall.

[Polly]

Great Teo ...





13:07:39 Teo out with an alarm call.
13:10:47 back

13:11


His harvest is not very full.

I'm off for today