The Cape Bird Club
Tern ringing report - Lourens River Estuary by Gordon Scholtz.
It seems strange now (winter 2009) to visit the Lourens River estuary where only a few weeks ago we were faced with thousands of screeching terns. The beach is deserted, leaving no signs of our summer visitors.
This season Common Terns were predominant with an estimated eight thousand congregating in January. We have also captured Swift, Sandwich and even a couple of White-winged Terns during the ten-year ringing project at this site.
Recapturing foreign ringed birds remains the highlight of the ringing project. During the past season amongst the 283 netted, we managed to recapture a Swedish ringed bird plus one from Estonia and a further three from Finland, bringing the number of birds ringed from that country to twenty five since the start of our beach programme.
The size of the tern roost remains a mystery – some years the flock is insignificant while other times there are literally thousands providing a spectacular display at the estuary. We have studied wind strength and directions, air and sea temperatures, moon and tide phases but have not found any specific links to the fluctuating flock sizes. It does, however, affect the ringing success rates.
Table 1 represents a record of all foreign ringed tern recaptures, and
Table 2 and graph indicate the total number of all tern species ringed per season.
Table 1.
|
Species |
Country of origin |
First ringed |
Recovered |
Time elapsed (yrs/mths/days) |
Distance |
|
Common |
Finland |
30/06/94 |
30/10/00 |
6y 4m 1d |
10610 km |
|
Common |
Finland |
26/06/96 |
11/10/00 |
4y 3m 16d |
10489 km |
|
Common |
Finland |
11/07/97 |
24/11/00 |
3y 4m 15d |
10510 km |
|
Common |
Finland |
19/06/00 |
2/12/00 |
5m 14d |
10488 km |
|
Common |
Finland |
24/06/00 |
2/12/00 |
5m 9d |
10516 km |
|
Common |
Finland |
03/07/99 |
9/12/00 |
1y 5m 8d |
10504 km |
|
Common |
Finland |
03/07/97 |
10/11/00 |
4y 4m 8d |
10774 km |
|
Common |
Finland |
22/06/99 |
3/12/01 |
2y 5m 12d |
10498 km |
|
Common |
Finland |
15/07/00 |
18/12/05 |
5y 5m 3d |
10573 km |
|
Common |
Finland |
30/06/02 |
20/01/06 |
3y 6m 20d |
10640 km |
|
Common |
Finland |
18/06/99 |
20/01/06 |
6y 7m 2d |
10519 km |
|
Common |
Finland |
29/06/05 |
20/01/06 |
6m 21d |
10830 km |
|
Common |
Finland |
26/06/01 |
28/01/06 |
4y 7m 2d |
10807 km |
|
Common |
Finland |
21/06/00 |
3/02/06 |
5y 7m 12d |
10592 km |
|
Common |
Finland |
11/07/99 |
20/01/06 |
6y 6m 9d |
10662 km |
|
Common |
Finland |
01/07/99 |
19/02/06 |
6y 7m 18d |
10830 km |
|
Common |
Finland |
28/06/99 |
19/02/06 |
6y 7m 21d |
10750km |
|
Common |
Finland |
29/06/07 |
02/03/08 |
9m 3d |
awaiting |
|
Common |
Finland |
11/07/06 |
17/01/09 |
2y 6m 6d |
10492 km |
|
Common |
Finland |
27/06/08 |
17/01/09 |
6m 20d |
10511 km |
|
Common |
Finland |
05/07/07 |
20/02/09 |
1y 7m 17d |
10542 km |
|
Common |
Finland |
27/06/08 |
20/02/09 |
7m 23d |
10507 km |
|
Common |
Finland |
26/06/08 |
14/03/09 |
8m 18d |
awaiting |
|
Common |
Finland |
27/06/02 |
14/03/09 |
6y 8m 17d |
awaiting |
|
Common |
Finland |
20/07/08 |
14/03/09 |
7m 25d |
awaiting |
|
Common |
UK |
19/08/84 |
30/10/00 |
16y 2m 11d |
9960 km |
|
Common |
Ireland |
07/06/01 |
26/11/02 |
1y 5m 19d |
9905 km |
|
Sandwich |
Ireland |
22/06/89 |
18/02/00 |
10y 7m 28d |
9918 km |
|
Sandwich |
UK |
19/06/97 |
24/11/00 |
3y 5m 6d |
10160 km |
|
Sandwich |
Scotland |
01/07/89 |
27/02/01 |
11y 7m 28d |
10510 km |
|
Sandwich |
N. Ireland |
24/06/91 |
27/02/01 |
9y 8m 5d |
10128 km |
|
Sandwich |
Scotland |
11/06/02 |
8/12/05 |
3y 6m 20d |
10351 km |
|
Common |
UK |
23/08/00 |
19/02/06 |
5y 6m 15d |
10048 km |
|
Common |
Lithuania |
18/06/99 |
16/12/00 |
1y 5m 30d |
9979 km |
|
Common |
Sweden |
03/07/85 |
10/11/01 |
16y 4m 8d |
10396 km |
|
Sandwich |
Sweden |
28/05/98 |
16/12/00 |
2y 6m 20d |
10179 km |
|
Common |
Sweden |
16/06/99 |
30/10/00 |
1y 4 15d |
10215 km |
|
Common |
Sweden |
05/07/00 |
10/11/00 |
4m 6d |
10384 km |
|
Common |
Sweden |
20/06/00 |
19/11/00 |
4m 30d |
10409 km |
|
Common |
Sweden |
awaiting |
20/02/09 |
awaiting |
awaiting |
|
Common |
Sweden |
awaiting |
08/03/09 |
awaiting |
awaiting |
|
Common |
Belgium |
19/09/00 |
24/11/00 |
2m 5d |
9619 km |
|
Common |
Belgium |
awaiting |
14/03/09 |
awaiting |
awaiting |
|
Sandwich |
Holland |
28/05/95 |
18/02/99 |
4y 8m 23d |
9800 km |
|
Sandwich |
Holland |
26/05/95 |
9/12/00 |
5y 6m 15d |
9799 km |
|
Common/Arctic |
Estonia |
25/06/90 |
20/01/06 |
15y 7m 5d |
10356 km |
|
Common |
Estonia |
27/05/99 |
19/02/06 |
6y 8m 25d |
10330 km |
|
Common |
Estonia |
19/06/08 |
14/02/09 |
7m 25d |
10326 km |
|
Sandwich |
Estonia |
22/06/01 |
23/02/08 |
6y 7m 29d |
10317 Km |
|
Sandwich |
Denmark |
03/06/96 |
20/10/06 |
10y 4m 17d |
10157 km |
|
Sandwich |
Germany |
01/06/99 |
15/12/07 |
8y 4m 15d |
9871 km |
Table 2.
|
Terns ringed at the Lourens River Estuary |
|||||||||
|
1999/00 |
2000/1 |
2001/2 |
2002/3 |
2003/4 |
2004/5 |
2005/6 |
2006/7 |
2007/8 |
2008/9 |
|
67 |
303 |
61 |
36 |
Nil |
1 |
278 |
32 |
28 |
283 |
photograph by Marilyn Scholtz
Sunset at the roost looking towards Cape Point.
photograph by Marilyn Scholtz
Day time activity, Hottentot Hollands Mountains in the background.
photograph by Francis Hannay
Behind the AECI fence looking towards the Strand.
