I dropped into one of the Merlin families that we ringed two weeks ago to check if they had successfully fledged. There were at least two juveniles (male and female) out of the nest and I suspect the other two chicks were in the area also. The adult female was on site the whole time. At one stage a male showed up which I initially thought was the adult male but it was apparent that it was a "brown" male. I naturally assumed it was one of the chicks. However I managed to get a few woeful record shots of it and on later inspection it proved to be a second-calendar/first-summer male. The light was atrocious at the time as it was raining for most the time. While the UK and to a lesser degree the east of Ireland has been experiencing a heat wave recently, typically for the west of Ireland we've had rain and windy conditions for the last while with temperatures struggling to even reach the high teens.
The male can be aged as a young bird by the newly moulted adult male-type black inner primaries contrasting with the old brown outer primaries and new grey scapulars, rump and tail although these aren't too easy to see in these crap shots. Female Merlin tend
to nest for the first time earlier than males. Two different studies put the average age of first breeding of female Merlin at 1.3
± 0.1 years and 1.3
± 0.6 years while the age of males was 2.3
± 0.1 and 1.9
± 0.7 years. Another study in Northumberland, UK found that 18% of breeding pairs contained a first year female but only 8 - 9% contained a first year male. Adult pairs tend to breed early in the year and are more productive than pairs with at least one first year bird.
One hypothesis for males taking that extra year to commence breeding compared to females is that they generally require more hunting experience as it largely falls on them to provide most of the food during the laying, incubation and early chick stages of the breeding cycle. Thankfully this young male was able to provide enough food to raise a brood of chicks in this instance. This isn't the first first year male that I've encountered in the small sample size of pairs I've had in Connemara with another first-year male seen two years ago. This relative high rate of breeding first year males may be a sign that all may not be well with the species here. It would suggest that there may be a lack of recruitment of adult males into the population i.e. that survival rates for males past their first year may be poor as females would certainly prefer older more experienced males. It's interesting to consider that the average life span of a Merlin is only 3 - 5 years. I'm assuming the breeding female was a at least a second-year or an older female but they are much more difficult to age but can be aged by the shape of tail feathers and the shape of the tail bars.
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| Second-calendar male Merlin. |
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| Second-calendar male Merlin. |
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| Second-calendar male Merlin. |
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| Second-calendar male Merlin. |
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| Adult female Merlin. |
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| Adult female Merlin. |
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| Adult female Merlin. |
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| Adult female Merlin. |
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| Adult female Merlin. |
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| Adult female Merlin. |
