Sunday, 10 May 2020

28th May 2020 Adult Swans

30th of May 2020  - Adult Swans sighted = 136

Scroll down- next page if you are looking for latest Cygnets news

The RAS season is on it's way.  This is checking all Swans within the project boundries roughly 40 Km from  Dublin and recording each individual which is ringed.  This information over years provides the annual survival totals.  Many thanks to all the regular ring readers and many thanks to the new ones.  I will update analysis periodically to the following over the coming week.  The season doesn't end till the end of the summer so hopefully the list will end up as 250+ Swans.  The more individuals the better the survival statistics in terms of margin of error.  New swans are being sighted most days

The following have been sighted and input so far since April 1st 2020 (22/05/2020).
(Table 1) All first ringed before my project started.  Some have had a colour ring added, 2 of them haven't.  If the metal ring number is in Blue they are confirmed as having attempted nesting this year. 

PLEASE NOTE:  I colour ring a lot of Juveniles which have a low survival rates compared with adults.  This is natural.

Out of the 32 Swans that have been in in the project since it began that fall into this category.
Confirmed dead  = 4
Seen in 2019 = 12
(22/05/2020) Seen so far in 2020 = 9
(So far, year on year, it is at 75% survival)  However the stats are done by a much more complex formula.

(Table 1) Mute Swans ringed before 2015


The following (Table 2) are swans ringed in 2015 which have been re-sighted already this season.  Further sightings are always welcome.  CAFP has the colour of the ring set as Grey.  This is because the colour ring is now missing.  Swan identified by the metal ring.
The number of swans metal ring in 2015 = 91
Confirmed dead  = 10
Seen in 2019 = 25
(22/05/2020) Seen so far in 2020 =18 (72% approx.)
(Table 2) Mute Swans Ringed in 2015

The number of swans metal ring in 2016 = 209
This 209 is a high percentage of cygnets which have a high mortality rate
Confirmed dead  = 20
Seen in 2019 = 64
Seen so far in 2020 = 24 (37% survival since last year)
This is where it it requires field work.  Those ringed in 2016 as Cygnets are now either nesting, looking for nest sites.  Therefore locating them is a challenge.  


The number of swans metal ring in 2017 = 127
Confirmed dead  = 7
Seen in 2019 = 49
Seen so far in 2020 = 22

(Table 4) Mute Swans Ringed in 2017



The number of swans metal ring in 2018 = 28
Confirmed dead  = 0
Seen in 2019 = 21
Seen so far in 2020 = 12




(Table 6) Ringed in 2019 before the RAS season ended
Mute Swans ringed since the end of the 2019 Census.




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