|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Coordinator: Albert de Jong Merijn Loeve Roland-Jan Buijs Thijs Horst Leon Kelder Mars Muusse |
|
location | April 24th, 2021: cluster of nests. | May 1st, 2022: adult female at nest. | April 24th, 2021: fight over nest 60-62-63. |
![]() |
![]() |
![]() |
|
eggs | April 24th, 2021: 3 eggs in nest. | May 13th, 2021: probable cachinnans egg. | April 19th, 2022: 3 eggs. |
![]() |
![]() |
![]() |
|
partner 1 | April 24th, 2021: adult female type nest 62??? | . | . |
![]() |
|||
partner 2 | May 13th, 2021: adult female hybrid type. | May 13th, 2021: adult female hybrid type. | May 13th, 2021: adult female hybrid type. |
![]() |
![]() |
![]() |
|
partner 2 | May 1st, 2022: adult female hybrid type. | May 1st, 2022: adult female hybrid type. | May 1st, 2022: adult female hybrid type. |
![]() |
![]() |
![]() |
|
food | May 13th, 2021: prey is Pike perch Sander lucioperca. | May 13th, 2021: prey is Rudd Scardinius erythrophthalmus. | May 17th, 2022: prey is Rudd Scardinius erythrophthalmus. |
![]() |
![]() |
![]() |
|
pulli | May 13th, 2021: 2 cachinnans pulli. | May 28th, 2021: dead chick in nest 62. | May 17th, 2022: chick NLA 5.625.104. |
![]() |
![]() |
![]() |
Visits and data.
date: | ||||||||
24-04-2021 | 2 partners present, both are most likely Caspian Gull cachinnans. But difficult to allocate birds to the nests. Nest allows trapping breeders, but early nest! | |||||||
3 eggs in nest. | ||||||||
egg no: | width (mm) | length (mm) | volume (cm3): | water test on April 24th: | ||||
A egg | 50,5 | 75,2 | 96,56 | 90 - floating, 3mm above surface | ||||
B egg | 51,8 | 72,8 | 98,35 | 90 - floating, 3mm above surface | ||||
C egg | 51,5 | 73,6 | 98,29 | 90 - floating, 2mm above surface | ||||
sum nest: | 293,20 | |||||||
26-04-2021 | Pictures taken from canoe, of several birds flying around nests 60-62-63. How to monitor, telescope? | |||||||
13-05-2021 | 2 chicks of nest 62 hide underneath Thistle Sircium cover, 45 cm's from nest. | |||||||
Fish prey: 1 possible Rudd 25 cm's, 1 week old. 1 predated (?) egg which seems to be cachinnans. | ||||||||
15-05-2021 | Many fish prey left-overs at nest: small Pike perch Sander lucioperca (taken for analysis). | |||||||
mass | head+bill (measurements Monika Ballmann) | |||||||
pullus | 236 gr | 64,1 | ||||||
pullus | 228 gr | 64,1 | ||||||
metal | tibia | head + bill | comments: | |||||
28-05-2021 | pullus | .5559412 | b-F|0 | 92,3 | Large pullus (16-18 days old), likely cachinnans from nest 60. | |||
pullus | .5559413 | b-F|1 | 95,3 | Large pullus, likely cachinnans from nest 60. | ||||
pullus | .5559414 | b-F|2 | 75,8 | Possibly argentatus, not necessarily from neighbour's nest, b-F|3 broken. | ||||
pullus | .5559415 | b-F|4 | 73,2 | Possibly argentatus, not necessarily from neighbour's nest, b-F|3 broken. | ||||
pullus | .5559416 | b-S|3 | 56,8 | Likely argentatus, from neighbour's nest. | ||||
pullus | .5559417 | b-S|4 | 57,2 | Likely argentatus, from neighbour's nest. | ||||
08-06-2021 | 3 adult Caspian Gulls present. No chicks visible from canoe, not on south nor on north side from water. They probably hide in blackberries complex. | |||||||
Visits and data 2022: Estimation egg laying: A-egg = April 13 2022. Estimating hatching = May 11 2022. |
||||||||
12-04-2022 | empty nest. | |||||||
15-04-2022 | 2 eggs in nest. | |||||||
egg no: | width (mm) | length (mm) | volume (cm3): | |||||
15-04-2022 | A egg | 50,1 | 68,1 | -- | ||||
15-04-2022 | B egg | 51,6 | 68,4 | -- | water test on April 27th: | |||
27-04-2022 | C egg | 50,3 | 66,8 | -- | floating halfway | |||
sum nest: | -- | |||||||
01-05-2022 | Adult at nest 62: very thin line on P5 but clear cachinnans influences | |||||||
09-05-2022 | 3 eggs: small crack in blue egg. | |||||||
17-05-2022 | 1 pullus and 2 eggs present. | |||||||
prey: half fish at nest probably Rudd. | ||||||||
metal code | darvic | mass | ||||||
pullus | NLA 5.625.104 | - | 165 | Large pullus (16-18 days old), likely cachinnans from nest 60. | ||||
22-05-2022 | Blue egg still present. No chicks found near nest, but hiding in Blackberry complex. | |||||||
egg sizes & volume 2023 | ||||||||||||
SPECIES | NEST | A_length | A_width | A_volume | B_length | B_width | B_volume | C_length | C_width | C_volume | TOTAL NEST: | known parents? |
cach x ? | 62-2023 | 70,1 | 51,2 | 92,52 | 70,3 | 51,8 | 94,98 | 67,9 | 51,7 | 91,38 | 278,88 | same as 2022 |
ring pulli: -- | laying A egg: -- | hatch A egg: -- | ||||||||||
catch: | date: | metal: | darvic: | mass: | wing: | head+bill: | bill: | gonys: | greytone: | |||
adult | 03-05-2023 | 6214904 | r-7.L | nn | 466 | 136 | 59,7 | 21,6 | 6 | female cach | ||
pullus | 18-05-2023 | 5556422 | G-7|3 | 116 | 52,6 |
62-2023 | ||
dam: | dam 1 west | |
location: | Is nest 62-2021/22. From cluster 60-62-63. | |
breeders: | cach x ? | |
OBSERVATIONS: | ||
09-04-2023 | nest: | no eggs, nest is ready. |
22-04-2023 | nest: | 3 eggs, water test = tip bottom 90 degrees; tip bottom 50 degrees, tip bottom 45 degrees. |
03-05-2023 | adult: | trapped female cach: r-7.L. |
eggs: | 3 eggs. | |
18-05-2023 | eggs: | 1 rotten egg. |
pullus: | 1 chick ringed is G-7|3, 1 chick dead in nest. |