Jo's picture

Goldcrest

Observed: 8th February 2010 By: JoJo’s reputation in BirdsJo’s reputation in Birds
Goldcrest
Description:

Europe's smallest bird, They arrive in Autumn from Scandinavian Countries and leave in March/April. Unbelievable considering it can fly non-stop over 500 kms.

Identifications
Species interactions

No interactions present.

Comments

Kluut's picture

Not quite right........

The firecrest is Europe's smallest bird. Goldcrests are resident in the UK - over half a million breeding pairs in the UK. Firecrests are also a UK-breeding species, with perhaps 100-200 pairs in S England.

I have a large conifer hedge around my garden and goldcrests are present all year - watched one this morning collecting feathers for its nest.

This bird is a male - hens have yellow crests.

DavidHowdon's picture

Goldcrest or Firecrest

According to Birds of the Western Palearctic (interactive edition) the goldcrest is the smallest.

There is a fair degree of overlap in their size ranges however.

Jo's picture

Not quite right...

Wikipedia and all the sites I have looked at state the firecrest is the second smallest bird and the Goldcrest as the smallest. I heard the south of England has some residents. Great to have they are a lovely and tough wee bird.

Kluut's picture

BTO

http://www.bto.org/

Ever since I was one hell of a lot younger, I have always been told that firecrest was smaller - BTO says they are the same length, wingspan and weight, as does HBW.

Jo's picture

There is only half a cm when

There is only half a cm when they are fully grown 8;5 for the goldcrest and 9 for the firecrest but they could weigh the same,

RoyW's picture

Very little between the two.

There is very little difference in size between Goldcrest and Firecrest, with considerable overlap in both size and weight - which explains why many books quote their size and weight as being the same.
When the range of size/weight for each species is given the smallest Goldcrests are slightly smaller than the smallest Firecrests (& the largest Firecrests are larger than the largest Goldcrests), so Goldcrest just about manages to claim the title as the smallest bird in Europe.

They are present in all parts of Britain throughout the year, but numbers are swelled by immigrants from the continent in autumn and winter.

anonymous spotter's picture

Smallest or runner up?

I reckon RoyW is right, the official difference will be less than the variation between individuals.
Whichever it is, it's a cracking photo.

Jo's picture

Thanks Roger.

Thanks Roger.

Kluut's picture

BTO and RSPB wrong?

Both BTO and RSPB say they are the same.

If you go to the BTO website, they have data from UK-rung birds - the differences vary betwen sexes and ages, but dimensions vary between the species by tens of microns, and weight varies by tens of milligrammes. And those figures are only meaningful because hundreds of firecrests have been measured, and thousands of goldcrests - using BTO figures and simple statistics, you'll find that there is no difference in size between the two species.

RoyW's picture

The BTO & RSPB are not wrong.

Like most bird books the BTO and RSPB quote approximate, averaged, figures for size and weight, and these are almost always rounded off to whole numbers - so the measurements quoted are not wrong. The size difference between the two is very small, with considerable overlap, but it has consistantly been shown to be there (and not just in BTO figures), so the Goldcrest is generally acknowleged as Europes smallest bird - barely pipping the Firecrest to claim this title. Both the BTO and RSPB quote the Goldcrest as the smallest british bird (see the 'Titbit', just above population details here; http://blx1.bto.org/birdfacts/results/bob13140.htm , and the first line here; http://www.rspb.org.uk/wildlife/birdguide/name/g/goldcrest/index.aspx ).

DavidHowdon's picture

BTO site

I'd not seen that bit of the BTO website before.

Clearly the ranges overlap and there is more intra-species variation than inter-species variation in size.

Interestingly the statistics on the BTO pages do show that male goldcrest has smaller mean wing length than firecrest but that for females they have the same mean wing length - although since the goldcrest has higher variance there will be more goldcrest at the smaller (and of course higher) end of the range.

Looking at the bottom of the ranges they are pretty much identical (although juvenile firecrest weight range does go lower than juvenile goldcrest). At the upper end the firecrest does tend to get a bit bigger (top end of ranges are higher).

But it is so close (and certainly indistinguishable in the field) that although I am happy that this data shows that goldcrest is the smallest I'd not argue with anyone who feels like saying they are identical (or that firecrest is smaller).

Kluut's picture

Read and compare

If you did but read the BTO data for both species, assuming you understand the statistics for what they are, you would see that the data collected from rung birds, says that they are the same size.
The BTO data gives averages for various measurements with ranges and standard deviations - none of them rounded to whole numbers - they are quoted to 2 d.p., 3 s.f. in total.
There is far more difference between individuals of the same species than there is on avergae between the species. VERY simple statistics.

RoyW's picture

Thanks -I had read the data, and I do understand the statistics.

As has already been said, there is very little difference between the size of the two species, and there is considerable overlap. All that I have done previously is pointed out that the Goldcrest is generally considered to be marginally the smaller of the two because the smallest individuals tend to be Goldcrests.
Like David says, it really isn't worth arguing against them both being the same size.

Jo's picture

I agree

Just go out observe,and enjoy.