A Bird’s Eye View

 Tanya Smith – Coordinator Drakensberg Crane Conservation Project EWT – reports on the recent Crane Survey:

At this time of the year when winter reaches its peak (or trough in terms of temperature), Wattled Crane breeding activity commences and this year it seems to be ‘full steam ahead’.  It would seem that the good rainfall in summer has laid the foundation for what appears to be an early start to a breeding season rife with activity and movement.

The Bateleurs once again assisted with an early season aerial survey over two days to locate approximately 50 breeding pairs of Wattled Cranes in the KwaZulu-Natal midlands and Drakensberg.  To say conditions were ideal over the two days of flying on the 10th and 11th June, would be an understatement, because for two days we experienced crystal clear conditions, light breezes and spectacular scenes of snow on the high berg.  However the real successes of the survey lie in two great stories that I will share with you a bit later.

Firstly though, I have to provide you with a sneak preview of the great data collected over the two days.  We were able to locate 41 of the 50 breeding pairs we were searching for and in addition to the pairs, we managed to locate 29 Wattled Cranes in 3 separate flocks, therefore bringing the tally to 111 adult Wattled Cranes located.  Of the 41 pairs found, 21 of these were found on nests and a further 8 pairs were found with a small chick each. Therefore more than 70% of the pairs located, were found in a state of breeding making this a noticeably early season as usually the majority of pairs will start nesting towards the end of June to early July.

Now for  the two great stories…

In the nick of time!

The first day of flying was focused on the Southern Drakensberg breeding sites and we checked approximately 25 sites.  The day started off great with several nests being found from the start and then we came overhead a large beautiful flood plain wetland, very characteristic of the Southern berg wetland systems, in search of two pairs of Wattled Cranes.   We quickly located a pair on the edge of the wetland and between the two adults was a tiny chick, possibly no more than 2 to 3 days old.

wattled cranes and chick

Photo 1: Wattled Crane pair in a grassland on edge of wetland with a 2-3 day old chick between them (Photo courtesy of Cobus Theron)

After we completed the survey for that day (about 2.5 hours after we saw this pair and chick), Cobus phoned the farmers to let them know the status of their Wattled Crane pairs.  When he chatted to the farmer with the pair and small chick, the farmer had said he was about to burn the wetland as part of his fire management.  Fortunately he was very concerned and willingly abandoned his plans to burn the wetland until the chick is a bit older.

When sacrifice is worth it!

In 2011 we partnered with Eastern Wetland Rehabilitation, a Section 21 company, to rehabilitate a wetland in the Nottingham Road area.  The wetland in question is home to a very productive pair of Wattled Cranes, and the nest site (and wetland as a whole) was threatened by a significant and very active head-cut that formed from an artificial drain within the wetland.

wetland head cut

Photo 2:  The depth of the head-cut, a highly erosive feature within this wetland that threatened the functioning of the wetland as well as the open pool of water within the wetland that is used by the Wattled Cranes for their nest site.

A head-cut is a backwards moving channel within a wetland that, if very active, can have a major impact on the functioning of a wetland by effectively draining it and removing water from the wetland at a faster rate than normal.  Head-cuts form usually as a result of a disturbance feature introduced to the wetland i.e. a road crossing or drain.  The unfortunate situation we found ourselves in was the head-cut in this wetland was very close to the active nest site (approximately 50m) and we faced a difficult decision:  Do we risk the nest site by causing major disturbance close to the nest site during the construction of concrete weirs that were needed in order to try and neutralise the head cut and fix the drains.  Also the main large structure at the headcut would be within 50m of the nest site for next 50 to 100 years (who knows) and this may cause enough of a deterrent to prevent the birds returning to nest.  Or do we risk the nest site by doing nothing?  Our research has shown that historic Wattled Crane nest sites/wetlands tend to be significantly drier than wetlands actively or currently used by Wattled Cranes for breeding.  Therefore the risk of the head-cut drying the wetland and possibly the open water area of the wetland, thereby making the wetland unsuitable for Wattled Crane breeding, was very real and significant.  Through many discussions with conservation officials and other experienced wetland scientists we decided to neutralise the head-cut in addition to the other weirs that were to be built along the drains.

Construction of the main head-cut structure commenced late 2011

wetland rehab process

Photo 3:  The full extent of the preparation required before concrete is thrown. The rehabilitation process (especially hard options like concrete) is quite daunting and hard to believe this is for the best.

Construction was completed in early 2012.

completed wetland headcut structure

Photo 4:  The completed structure at the start of the head-cut, therefore neutralising any further movement of the head-cut upstream within the wetland.

All the activity around the wetland continued into the usual courtship period for Wattled Cranes (April) and therefore we knew there was little to no chance of the Wattled Cranes breeding here in the 2012 season. We sacrificed one season, and hoped that the birds would return to breed in 2013.

As we approached this site during this aerial survey on the second day, I held my breath, hoping and praying we would see Wattled Cranes in or near the wetland!  Well, the birds did one better – they were nesting!  They were nesting in their usual site, within 50m of the structure that was completed nearly 18 months earlier!  I cannot describe the importance of this sighting and the feeling of… ‘It was worth it’!

With the support of the National Lottery Fund, the Eastern Wetland Rehabilitation team, wetland scientists and more, we were able to prevent a significant threat to a breeding pair of Wattled Cranes, one pair of only 80 left in the country!  And thanks to the Bateleurs for allowing us the opportunity to document this achievement from the air. Deep thanks and gratitude to our pilot, Barry de Groot, it was a pleasure and I’d say, hands down, the best survey yet!

wetland - wattled crane nest and headcut

Photo 5:  An over head view of the concrete structure that has neutralised an active head-cut and the location of the open water and nest platform of a pair of Wattled Cranes

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One thought on “A Bird’s Eye View

  1. Mrs C.J. King

    What an exciting and interesting post! Thank you so much and well done Tanya.

    Mrs. C. J. King,

    Inchbrakie,

    P.O.Box 196,

    Nottingham Road,

    Kwa-Zulu Natal, 3280,

    SOUTH AFRICA.

    S – 29 21′ 189″

    E – 29 55′ 798″

    ALTITUDE:- 4,326feet (1,442metres)

    Tel: 00 27 (0)33 815 9518

    Mobile: 00 27 (0)82 941 3533

    E-MAIL C.J.K@bundunet.com

    _____

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    Reply

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