POPULATION SIZE AND DISTRIBUTION OF BLUE, GREY CROWNED AND WATTLED CRANE IN KWAZULU-NATAL, SOUTH AFRICA, DETERMINED BY AN AERIAL SURVEY DURING

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1 POPULATION SIZE AND DISTRIBUTION OF BLUE, GREY CROWNED AND WATTLED CRANE IN KWAZULU-NATAL, SOUTH AFRICA, DETERMINED BY AN AERIAL SURVEY DURING July 2007 ENDANGERED WILDLIFE TRUST - KWAZULU-NATAL BIODIVERSITY PROGRAMME AND KWAZULU-NATAL CRANE FOUNDATION Andre Rossouw / Kevin McCann August 2007

2 INTRODUCTION As part of the annual monitoring programme in KwaZulu-Natal, the aerial surveys with Ezemvelo KwaZulu-Natal Wildlife have given us useful information regarding population trends of cranes over the years. It is important in any conservation programme to regularly monitor the population trends so as to determine whether your conservation actions are being effective. For this reason an annual crane aerial census is performed throughout KwaZulu-Natal, as this covers one of the most important crane regions in the country for all three species of crane. Since 2005, other species were also included in the survey, which included Oribi antelope, Denham s Bustards, Secretary Birds and Goliath Herons. The benefits of an aerial as apposed to a ground census are obvious, as a far larger area can be censused in a shorter period of time. This is very important, as these birds are capable of flying over large distances, potentially leading to duplications of counts the longer the time over which the count is performed. In addition, the survey was used to identify any illegal or potentially illegal agricultural developments. METHODS This aerial census has been performed over the past 12 years censusing all three crane species in all key crane regions from Wakkerstroom and the Slang river catchment in the north through to Kokstad and the Cedarville flats in the south (see Figure 1 showing the regions covered during each of the survey days). During 2007 the aerial surveys were conducted over 5 days (see Table 1) censusing all the key regions (see Figure 1 for coverage) for the above mentioned species throughout KwaZulu-Natal during July, totalling hours of flying. Table 1: Technical details of the June 2006 aerial survey in KwaZulu-Natal Aircraft type Average speed Average height Pilot Navigator Day 1 (16/07/07) Midlands (west Mooi River / Nottingham Road) Observers Day 2 (17/07/07) Midlands (east Greytown) Observers Day 3 (18/07/07) Himeville / Underberg Observers Day 4 (19/07/07) Kokstad / Cedarville Observers Day 5 (25/07/07) northern KZN Observers Cessna 182 (high wing) 90 km/hour 100m Greg Nanni (KZN Wildlife) Andre Rossouw 5.1 hours Kevin McCann / Katerina Wojtaszekova 4.4 hours Kevin McCann / Leon Theron 4.0 hours Kevin mccann / Richard Schutte 4.5 hours Kevin McCann / Richard Schutte 4.45 hours Brian Reeves / Kirsten Oliver

3 Day 5 northern KZN Day 3 Himeville / Underberg Day 2 Midlands (east) Day 1 Midlands (west) Day 4 Kokstad / Cedarville Figure 1: Map of KwaZulu-Natal province showing the separate regions covered during the 5 flying days during the aerial survey. The aims of the current aerial surveys are as follows: Determine the total number of Wattled Cranes in the province; Determine the status of Wattled Crane breeding activity; Determine the population trends for Grey Crowned Crane in the province; Locate as many Blue Crane flocks as possible for future follow-up on the ground by landowners. Locate populations of Oribi, Denham s Bustard, Ground Hornbill, Goliath herons, Fish Eagle and Secretary Birds. The same areas of the province have been covered over the previous 7 years over a five day period, with each flight lasting an average of five hours, as indicated in Figure 1. An attempt was made to keep all recorders and observers the same, to

4 remain as standard as possible. The survey was carried out during the winter months between the middle of June and July, and followed the following protocol: On each survey day, a set route was followed between all known active and historic Wattled Crane breeding sites within the demarcated area for that survey flight (refer to Figure 1 for these demarcated areas). This allowed every Wattled Crane breeding site to be assessed and the determination of a total population number for Wattled Cranes. Along these set routes, specific blocks were flown intensively to determine a total count of all cranes (especially Grey Crowned Cranes) within the block. This allowed the determination of a density value for Grey Crowned Crane (the area of each block was determined, allowing the density value to be calculated). The specific blocks flown intensively are shown in Figure 2. Blue Crane pairs, family groups and flocks found along the route or within the blocks were also recorded. Additional species recorded:- Several additional species were also recorded during the aerial survey, which included Oribi, Denham s Bustards, Secretary Birds, Ground Hornbill, Goliath Herons and any raptor nests (e.g. Fish Eagles, etc.) For every crane or other species observed, the following information was recorded:- Species Number of individuals (age class if possible) Activity (e.g. breeding, nest, foraging, etc.) Type of habitat GPS coordinate This information was stored on a laptop, allowing background maps and set routes to be followed. Data was logged in real-time, allowing the prevention of duplicate counting. The detail route followed during each of the survey sessions was determined and plotted using the Garmin GPS track log function. This allowed the standardisation of all future survey routes in each demarcated area throughout the province.

5 Figure 2: Map of KwaZulu-Natal showing the location of all species sighting data from the 2007 survey, as well as the flight blocks (red polygons).

6 RESULTS 1. Population numbers, structure and distribution The aerial survey in KwaZulu-Natal consisted of a total count. 453 Blue Cranes, 2718 Grey Crowned Cranes and 201 Wattled Cranes were sighted during the aerial survey in July 2007 forming the total population numbers for the province. Additional species sightings included 84 Oribi, 63 Deham s Bustards, 9 Secretary Birds and an electrocuted Cape Vulture under a powerline. Figure 3 shows the distribution of the cranes between the different regions flown Number Day 1- M idlands West Day 2 - M idlands East Day 3 - Underberg Day 4 - Kokstad Day 5 - N KZN Flying day - KZN region Grey Crowned Crane Blue Crane Wattled Crane Figure 3: The number of Blue, Grey Crowned and Wattled Cranes seen during the different survey days covering different regions of the province. 1.1 Blue Crane - The following Tables 2 and 3 show the numbers of Blue Cranes sighted during the aerial survey, together with a break down of the population structure. Table 2: The numbers of Blue Cranes seen during the different survey flights throughout KwaZulu-Natal, showing the relative population structure.

7 Region Singles Pairs Pair + 1 Pair + 2 Flocks Total juvenile juveniles Midlands (east) Greytown Himeville / Underberg Kokstad / Cedarville Midlands (west) - Mooi River/ Nott Rd Northern KZN TOTAL Table 3: Frequency of observed group sizes of Blue Cranes in KwaZulu-Natal, July Group size Frequency of Sum of birds in group % of population Observation 1 (singleton) % 2 (pair) % 3 (pair + juv) % 4 (pair+ 2juv) % % % % % % % % % % % % A total of 453 Blue Cranes were sighted during the 2007 aerial survey. This has been the highest count through the past 7 years, compared to the 2006 count of 298, 2005 count of 415, 2004 count of 325, the 2003 count of 311, and the 2002 and the 2001 aerial survey results of 364 and 363 Blue Cranes respectively. These birds showed a strong tendency to be found in flocks of larger than 20 individuals (83.4%% of individuals were found in these large flocks). A total of 94% of the population was located in non-breeding flocks, compared with 98.6% in 2006, 90.8% in 2005, 92.1% in 2004, 90.0% in 2003, 94.5% in 2002 and 89.5% during This is understandable due to their nature of forming large flocks during the winter months

8 and moving between traditional foraging areas. This portion of the Blue Crane population was characterised by a few, large flocks (10 flocks contributing 94% of the KwaZulu-Natal population). Figure 4: The distribution of Blue Crane sightings during the 2007 crane aerial survey in KwaZulu-Natal. 1.2 Grey Crowned Crane The following Tables 4 and 5 show the numbers of Grey Crowned Cranes sighted during the aerial survey, together with a break down of the population structure.

9 Table 4: The numbers of Grey Crowned Cranes seen during the different survey flights throughout KwaZulu-Natal, showing the relative population structure. Region Singles Pairs Pair + 1 Pair + 2 Pair + 3 Flocks Total juv juvs juvs Midlands (east) (6) 185 Greytown Himeville / Underberg (8) 677 Kokstad / Cedarville (19) 1478 Midlands (west) - Mooi (3) 183 River/ Nott Rd Northern KZN (4) 195 TOTAL Table 5: Frequency of observed group sizes of Grey Crowned Cranes in KwaZulu- Natal, June Group size Frequency of Sum of birds in group % of population Observation % % % % % % % % % % % % % % % % % % % % % % % % % % % %

10 % % % % % % % % % % % % % % A total of Grey Crowned Crane were sighted during the 2007 aerial survey, compared to the 2098, 2293, 1 929, 2 128, and sighted respectively during the 2006, 2005, 2004, 2003, 2002 and 2001 surveys, covering the same areas as the last 5 years. Only 5% of the population were found in pairs or family groups outside of non-breeding flocks, compared with 6.6%, 11.1%, 12.8%, 11.4%, 13.5% and 10% during 2006, 2005, 2004, 2003, 2002 and 2001 respectively. The remainder of the population was found in 40 separate flocks throughout the province, numbering between 8 and 181 individuals. The average flock size was 65 individuals, which is higher than previous years, e.g. in 2006 the ave. flock size was 59, in 2005 ave. flock size of 58 and 2004 ave. flock size of 45. The southern regions of the province, covering the Himeville / Underberg regions and the Kokstad / Cedarville regions appear to be the most important regions in the province for Grey Crowned Cranes.

11 Figure 5: The distribution of Grey Crowned Crane sightings during the 2007 crane aerial survey in KwaZulu-Natal. 1.3 Wattled Crane The following Tables 6 and 7 show the numbers of Wattled Cranes sighted during the aerial survey, together with a break down of the population structure. Table 6: The numbers of Wattled Cranes seen during the different survey flights throughout KwaZulu-Natal, showing the relative population structure. Region Singles Pairs Pr + Pr + Pr + Flocks Total Nest chick fledged Midlands (east) (1) 39 Greytown Himeville / Underberg Kokstad / Cedarville

12 Midlands (west) - Mooi (4) 114 River/ Nott Rd Northern KZN TOTAL Table 7: Frequency of observed group sizes of Wattled Cranes in KwaZulu-Natal, June Group size Frequency of Sum of birds in % of population Observation group % % 2 + nest % 2 + chick % % % % % % % A total of 201 Wattled Crane were sighted during the 2007 aerial survey, compared to 221, 224, 202, 208, 188 and 183 during the 2006, 2005, 2004, 2003, 2002 and 2001 surveys respectively. Therefore, the Wattled Crane population has remained relatively stable over the past 7 years. Due to the winter months being the main breeding period of the Wattled Crane, it is not surprising that 68.1% of the population were found in pairs or were breeding (either had a nest or unfledged chick) or still had their fledged youngster from last breeding season. This is slightly higher compared to previous years, which was 52.4% in 2006, 65.6% in 2005, 55.5% in 2004, 51.4% in 2003, and 64.4% in A lower proportion of the population compared to the last five years was located in non-breeding flocks, i.e. 31.9% in 2007 compared to 45.3% in 2006, 34.4% during 2005, 36.6% during 2004, 36.9% during 2003 and 35.6% during the 2002 survey, consisting again of 5 separate flocks in 2007, with an average of 12 individuals, which is far lower than the previous years of 20 individuals. The largest flock of Wattled Crane sighted during the 2007 survey consisted of 18 individuals and was seen in the Mooiriver district.

13 Figure 6: The distribution of Wattled Crane sightings during the 2007 crane aerial survey in KwaZulu-Natal. Assessment of Wattled Crane Breeding Activity Sixty of the 68 known breeding pairs in KwaZulu-Natal were located during 2007 survey, compared to 54 during 2006, 64 during 2005, 56 in 2004, 57 in 2003, 53 in 2002, 58 located in 2001 and only 46 during A lower proportion compared to 2006 (43.3% in 2007 compared to 53.7% in 2006), were pairs in their breeding territories, but had not yet commenced breeding this year. However it compares well to the 42% and 43% of the 2005 and 2004 surveys but is higher then the 2003 and 2002 surveys of 28.8% and 25.5% respectively. Only 13 pairs had nests, with 7 pairs having a clutch of 1 egg, 4 with a clutch size of 2 eggs and 2 unknown clutch sizes. Eight pairs of Wattled Crane had unfledged chicks, all less than 6 weeks old, while 9 pairs still had last year s youngster with them on the breeding territory. Table 8 shows

14 the various Wattled Crane pairs located and their relevant breeding status during the survey. 1.4 Trends in Crane populations Due to the fact that previous surveys have determined total count information, where no guarantee of each flight covering the exact same area, trends in populations could not be determined. Therefore, from 2005 specific blocks were flown allowing the determination of densities for prescribed areas of the province. These blocks were shown in detail in the 2005 KZN aerial survey report, while Table 9 indicates the densities of both Blue and Grey Crowned Cranes for each block (note that these densities are per 1000 hectares). Table 9: Densities of Blue and Grey Crowned Crane for each prescribed block flown during the 2006 aerial survey (represented as cranes per 1000 hectares). Block Block BC No. GCC Region Block Name No. BC no. size (ha) densities GCC densities Greytown Block 1 Karkloof Block 2 Umvoti Vlei Block 3 Pi Delta Block 4 Fordoun Midlands Block 1 Baynesfield Block 2 Boston Block 3 Umgeni Vlei Block 4 Fort Nottingham Block 5 Mearns Underberg Block 1 Himeville Block 2 Clovelly Block 3 Riverlea Block 4 Ideal View Block 5 Fearnley Kokstad Block 1 Franklin Block 2 Kokstad W Block 3 Cedarville Block 4 New Amalfi N KZN Block 1 Winterton Block 2 Colenso Block 3 Ravensdale

15 Block 4 Besters Block 5 Chelmsford Block 6 Nooitgedacht Block 7 Blood River Vlei TOTAL In terms of Blue Crane densities, only 3 blocks produced higher densities than most, which included the Cedarville, Colenso and Ravensdale blocks. Grey Crowned Crane was far more evenly distributed throughout the province, with 10 blocks having densities higher than 10 cranes per 1000 hectares. The 2006 and 2007 Grey Crowned Crane densities compare relatively well with one another as indicated in figure 7. In only three blocks Baynesfield, Franklin, and Blood River Vlei there is a significant difference between the densities for 2006 and In all three cases the density for 2006 is notably higher compared to In two blocks, Cedarville and Nooitgedaght the density for 2007 is notably higher compared to Density( No./1000ha) Karkloof Umvoti Vlei Pi Delta Fordoun Baynesfield Boston Umgeni Vlei Fort Nottingham Mearns Himeville Clovelly Riverlea Ideal View Flight Blocks Fearnley Franklin Kokstad W Cedarville New Amalfi Winterton Colenso Ravensdale Besters Chelmsford Nooitgedacht Blood River Vlei Figure 7: A comparison of the densities for Grey Crowned Crane in the different blocks for the 2006and 2007 aerial survey. 1.5 Other Species

16 Additional species located and recorded during the 2007 aerial survey included Oribi antelope, Secretary Birds and Denham s Bustards. No Ground Hornbill, Goliath heron and Fish Eagles were located. Figure 6 indicates the location of these species during the 2007 survey, while Table 10 shows the distribution of records throughout the different regions flown. Table 10: Numbers of Oribi, Secretary Birds and Denham s Bustards recorded during the 2006 aerial survey. Region Oribi Secretary Birds Denham s Bustard Goliath Heron Fish Eagle Northern KZN Himeville / Underberg Kokstad / Cedarville Midlands (west) - Mooi River/ NR Midlands (east) Greytown TOTAL

17 Figure 6: Map of KwaZulu-Natal showing the location of Oribi, Secretary Bird and Denham s Bustard records for the 2007 aerial survey. ACKNOWLEDGEMENTS We would like to thank Ezemvelo KZN Wildlife for their generous support of this valuable conservation monitoring project in KwaZulu-Natal, and the use of the Cessna plane. Endangered Wildlife Trust August 2007