Cape Vulture (Gyps coprotheres): Revise global status?

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14 Responses to Cape Vulture (Gyps coprotheres): Revise global status?

  1. Warren Goodwin says:

    I support the current proposal for re-assessment of the Cape Vulture (Gyps coprotheres) to ‘Vulnerable’ status.

    During the 2015 review, some evidence came to light of a stabilizing trend within the Cape Vulture population in South Africa. This was in the form of a paper by Patrick Benson (see ref). At the time it was proposed that retention of ‘Vulnerable’ status was perhaps more appropriate for this species, however as a compromise, it was eventually decided that the status of ‘Endangered’ be applied. A contributing factor at the time was the fact that around 80% of the population occurs within the borders of South Africa, Lesotho and Eswatini (Swaziland) and that the species was listed as ‘Endangered’ according to The 2015 Eskom Red Data Book of Birds of South Africa, Lesotho and Swaziland. The extinction of the satellite Namibian breeding colony was also taken into account at the time.

    Recently published results of ongoing monitoring from 2010 to 2019 at northern breeding colonies (by Hirschauer et al.) add further support to the assertion of a relatively stable and even increasing core population. Anecdotal evidence for other regions also suggests a similar trend, however it does seem that a more holistic monitoring approach is required. The recent genetic study (by Kleinhans and Willows-Munro) has also provided further insight into population dynamics.

    Although monitoring methods may not be standardized between different groups involved, such data gathered over a relatively long time span is nevertheless informative. Evidence is indeed mounting that this species does not meet the criteria for its current status.

    It would seem that the ongoing long-term efforts of those individuals and organizations involved in the conservation of the Cape Vulture may well have had a sustained positive effect on the population, and that while a number of threats still exist, this species should be reverted to ‘Vulnerable’ status. A great achievement in light of current circumstances.

    References:

    Benson, P. C. (2015). A survey of Cape Vulture breeding colonies in South Africa’s northern provinces (Transvaal Region) – an update 2013. Ornithol. Observations 6: 31–36.

    Hirschauer, M.T., Wolter, K., Howard, A., Rolek, B.W. and McClure, C.J.W. (2020). Population growth rates in northern Cape Vulture Gyps coprotheres colonies between 2010 and 2019. Bird Conservation International.

    Kleinhans, C. and Willows-Munro, S. (2019). Low genetic diversity and shallow population structure in the endangered vulture, Gyps coprotheres. Scientific Reports 9: 5536.

  2. Walter Neser says:

    I strongly oppose the current proposal for re-assessment / change of the Cape Vulture (Gyps coprotheres) status to ‘Vulnerable’.
    There is a very high likelihood that published numbers from more recent studies are showing higher numbers in core areas for several reasons.
    Changes in effort
    Possible over estimates (birds on cliff presumed to be breeding when not)
    Movement to core areas, while peripheral colonies go extinct.
    The breeding range has shown a marked contraction towards to core.
    Recent extinctions such as the Roberts Farm colony, in all likelihood bolstered numbers in other colonies in the core, and these extinctions / emigrations is not considered in counts showing increases in adjacent colonies.
    Until the status and trends of the population can be better assed and movements / emigrations quantified, no change in status should be made.
    To improve population data;
    data deficiencies of the satellite colonies must be addressed,
    a comprehensive population model built, based on broader long term monitoring,
    increase emphasis on, and implementation of standardised of monitoring,
    conduct an annual start of season training meet to “calibrate” observers.

    Furthermore, threats to this species are increasing, not decreasing:
    increasing number of powerlines, windfarms, loss of habitat and safe food, poisoning, trade / muthi, lead, lack of adequate consequences to perpetrators of wildlife crimes and more.
    Without increased conservation efforts, to combat this, the species will decline. Vultures have proven that they are very susceptible to singular events which can have massive effects on populations.

    Down listing will also have a negative effect on conservation efforts, while making both individuals and corporates that pose direct threats to the species less “vulnerable” themselves, as their actions would only be against a vulnerable species rather than an endangered species. EIA considerations will be different, which could bring disturbance closer to breeding sites, and criminals could face lower penalties.

    Additionally, this reported population stability may also in part be attributed to massive recent conservation efforts in the core areas, and though these efforts will hopefully continue, they must not be taken for granted in current times. Small changes can sometimes have massive effects on the status of a species.

    • Warren Goodwin says:

      We should be cognisant that this assessment has been made according to the latest available published data and Red List criteria.

      While the published data do suggest that a continued decline is likely, this figure is significantly lower than previously estimated. Genetic data has now also confirmed that there is considerable movement between the colonies, which effectively form a single population. Satellite colonies are often situated at sub-optimal sites and will naturally decline as birds move to the core areas. Depending on the circumstances, they may, or may not return once the core population has recovered and capacity is once again reached at prime sites.

      While threats do still exist, the overall pattern is one of a positive trend. This must surely be due (at least in part) to the great work that all involved have done for this species, both recently and over past decades. In my view a re-assessment to ‘Vulnerable’ should be taken as a sign that all this effort and funding continues to bear fruit, and that there is real hope for conservation of this species, as long as the work continues.

  3. Andre Botha says:

    I have been asked to share the following monitoring data from the largest known breeding colony for this species by the monitoring team who seem to not be able to access the link and post this data themselves. This is unpublished data submitted on behalf of Johan van Wyk and David Pretorius between 2006 and 2020 for the Blouberg CV breeding colony is as follows:

    Summary of count results
    Nest sites Chick count (Aug) Fledgling count (Oct)
    2006 626 394
    2007 522 401
    2005 511 287
    2009 433 312
    2010 533 364
    2011 572 432
    2012 1046 967
    2013 1161 1017
    2014 1345 1155 1055
    2015 1433 1229 1081
    2016 1454 1330 1207
    2017 1471 1312 1085
    2018 1482 1352 1203
    2019 1483 1315 1213
    2020 1483 1391 1212

    This upward trend in the largest known breeding colony for the species within its range supports the team’s agreement with the re-assessment and down-listing of the species to Vulnerable as suggested.

  4. Ryno Kemp says:

    We strongly oppose the current proposal for re-assessment of the Cape Vulture (Gyps coprotheres) to ‘Vulnerable’ status. We feel the decision to change the status of Cape Vultures can cause more harm than good. We will explain in more detail why we think the proposed re-assessment will be catastrophic to Cape Vultures.

    The publication by Benson (2015) and Hirschauer et al. (2020) that Warren Goodwin highlighted showed that the populations are stable with a slight increase in population numbers in the North-Eastern populations. In addition, Benson and McClure (2019) also support the recent rise in numbers at Kransberg since 2003. However, these numbers are still not above the numbers recorded during 1980 and earlier. As Walter Neser mentioned, colonies may be stable and showing slight increases in past years as the smaller colonies are becoming abandoned with birds joining larger colonies. Recent monitoring in June 2021 recorded numbers dropping from 2020 by 27% at Skeerpoort, North West, 16% at Kransberg, Limpopo and 8% at Manutsa, Limpopo (Wolter et al. unpublished). The basis for the suggested change is less than a handful of articles only covering a number of colonies, without a detailed understanding of what the whole population is doing, with a specific lack of knowledge regarding the colonies of the Eastern Cape, KwaZulu Natal, Botswana, Lesotho and Mozambique. The papers highlighted suggest that we first need to make a detailed population estimate before assuming that the population is increasing or stable. Another astonishing thing is that no one is concerned that the majority of breeding pairs are found at a handful of colonies putting Cape Vultures at a higher risk of local extinction than any other African vulture species.

    A further consideration is that Cape Vultures spend approximately 90% of their time outside protected areas, magnifying the anthropogenic threats (e.g., renewable infrastructure, habitat fragmentation, poisoning, power line infrastructure, etc.) they are facing. Ogada et al. (2016) highlighted that poisoning is one of the main threats these birds face, and we know that poisoning can kill hundreds of birds during one poisoning event as a recent poisoning event in Botswana. The second main threat Ogada et al. (2016) highlights is the muti trade, with a recent study estimating that traditional health practitioners use 400-800 vultures a year just in the Kruger to Canyons Biosphere Region of South Africa (Mashele et al. 2021) with the third largest Cape Vulture Colony in this region. The third main threat is power line infrastructure, with various authors having shown the threat of power lines on Gyps vulture species (Bromfield et al. In Press; Aspenström et al. In Press). Power line related incidents sometimes go undetected compared to other mass mortality events because of single events scattered across the landscape. Aspenström et al. (In Press) showed that these birds encounter power line infrastructure daily, which magnifies the threat of power lines.

    Another reason why we strongly oppose the current proposal for re-assessment of the Cape Vulture to ‘Vulnerable’ status is that of climate change. Phipps et al. (2017) is the only publication to the best of our knowledge that has addressed and shown that based on current movement data, there will be a contraction around the three biggest Cape Vulture colonies by 2050. These areas will become too hot for them to occupy and will have to shift southwards to less suitable smaller colonies to avoid lethal dehydration and heat stress. In addition, Engelbrecht et al. (2015) showed that by 2071-2100 South Africa would be 6C warmer than what we are currently experiencing and could be catastrophic for such large birds (Blanckenhorn 2000). This is a threat that is not even considered yet for Cape Vultures or any vulture species for that matter and is an area of research that will need to be addressed before consideration can be made on the IUCN status change of Cape Vultures.

    With this in mind, the question to be addressed is whether this species has recovered enough to avoid another potential collapse in population numbers when the species status gets changed to ‘Vulnerable’ with so much unknown of what is actually going on. Should this change go through, it will be catastrophic for the species and the ecosystem they serve. The priority of this species will be lost, and it will become more and more challenging to obtain funding to protect the species. This is already a difficult feat in the current economic times as it is, and adding additional pressure on the funding opportunities for this species will, quite frankly, be a mistake. Therefore, taking all the above information into account, we believe strongly that it will be a huge mistake to change the status of the Cape Vulture to “Vulnerable”. We, therefore, urge Birdlife International to reconsider the proposal as it will be catastrophic to the conservation of Cape Vultures and could lead to yet another collapse in their numbers.

    Thanks
    Ryno Kemp, Kerri Wolter, Caroline Grace Hannweg

    • Ryno Kemp says:

      Reference:
      Benson, P.C., 2015. A survey of Cape Vulture breeding colonies in South Africa’s northern provinces (Transvaal Region)-an update 2013. Biodiversity Observations, pp.31-36.

      HIRSCHAUER, M.T., WOLTER, K., HOWARD, A., ROLEK, B.W. and MCCLURE, C.J., Population growth rates in northern Cape Vulture Gyps coprotheres colonies between 2010 and 2019. Bird Conservation International, pp.1-10.

      Benson, P.C. and McClure, C.J., 2020. The decline and rise of the Kransberg Cape Vulture colony over 35 years has implications for composite population indices and survey frequency. Ibis, 162(3), pp.863-872.

      Ogada, D., Shaw, P., Beyers, R.L., Buij, R., Murn, C., Thiollay, J.M., Beale, C.M., Holdo, R.M., Pomeroy, D., Baker, N. and Krüger, S.C., 2016. Another continental vulture crisis: Africa’s vultures collapsing toward extinction. Conservation Letters, 9(2), pp.89-97.

      Mashele, N., Thompson, L.J. and Downs, C.T., 2021. Uses of Vultures In Traditional Medicines In the Kruger To Canyons Biosphere Region, South Africa. Journal of Raptor Research.

      Phipps, W.L., Diekmann, M., MacTavish, L.M., Mendelsohn, J.M., Naidoo, V., Wolter, K. and Yarnell, R.W., 2017. Due South: A first assessment of the potential impacts of climate change on Cape vulture occurrence. Biological Conservation, 210, pp.16-25.

      Engelbrecht, F., Adegoke, J., Bopape, M.J., Naidoo, M., Garland, R., Thatcher, M., McGregor, J., Katzfey, J., Werner, M., Ichoku, C. and Gatebe, C., 2015. Projections of rapidly rising surface temperatures over Africa under low mitigation. Environmental Research Letters, 10(8), p.085004.

      Blanckenhorn, W.U., 2000. The evolution of body size: what keeps organisms small?. The quarterly review of biology, 75(4), pp.385-407.

    • Warren Goodwin says:

      Just a note that this assessment is specific to the Cape Griffon and thus figures that lump both local Gyps species together may be misleading, as threats to each are generally disproportionate.

      Reduction in breeding numbers noted this season at a few sites could well be due to emigration to other colonies within the population, or simply due to other factors related to this particular breeding season. It is the long-term trend across the whole population that is really informative.

      In addition, it is well known that truly accurate climate change models are notoriously difficult to construct, due to the number of complex variables and multiple unknown factors.

  5. Peter Mundy says:

    I will insist on calling this species the Cape Griffon. Also I do not agree with ‘generation length’, it should be 6 years.
    The CG is the best studied Old World vulture, with regular counts being started in 1973, and the only one where any kind of realistic numbers are available. Regretfully a simultaneous census of all colonies has yet to be attempted, so the astounding increase at Blouberg may indeed be partly coming from other colonies. A couple of comments first: the Zimbabwe ‘colony’ has disappeared even though there are still CGs in the country, perhaps up to 25 (?), because of human disturbance. The mapped range is too far north in Angola and Zambia. The threats as listed by Walter are correct and likely as he says to continue though with fluctuating impacts.
    We first put the CG on to the red data list in 1979, with somewhat of a thumb-suck for a species’ estimate; the threats as listed above have been acting since then. Now it has to be acknowledged that the breeding adults are increasing with ongoing censuses. This is the key measure of successful conservation, or ‘stability’, and indicates that any rates of decline published in the past are ‘modelled’ and hypothetical.
    Overall the species is accurately portrayed as VU and certainly not as EN, whether or not this could affect funding or interest or indeed conservation itself of the bird. We must not cry ‘wolf’ when there are 10 000 or more adults, and increasing, and not be afraid to face the reality. The CG is endemic to southern Africa, and will therefore continue to be actively studied, protected, and conserved.

  6. Kevin Shaw says:

    Piper (1994) estimated that the global population was 4400 breeding pairs. He also provided global estimates in various papers for 2000 and 2013 of 3000+ and 3000 breeding birds, respectively and suggested that the global population declined by 15% between 1980 and 2000. These estimates were most likely were based on feedback from the various colony coordinators at annual meetings of vulture conservationists. There is another global population estimate for 2013 of 4700 breeding pairs mentioned by Allan (2015). This was most probably from an attempt by the Cape Vulture Task Team that had a meeting that year to estimate the global population size. As this is about the same figure of Piper (1994) it would suggest that the population may have recovered.
    The population trends of Cape Vulture for the period 2012-2019 for six of the largest colonies in the north-east (data obtained from published papers and colony “counters”) together with the south-west population (Potberg) indicates an increase of 4% per annum. Unfortunately, although several the south-east colonies are monitored no good data sets could be obtained.
    Data from Oribi Gorge Colony (about 94 breeding pairs) was obtained, and the count coordinator did indicate that numbers were increasing. This is higher than the 2011 estimate (39 breeding pairs) for the colony which substantiates the coordinators statement. It is, however, possible that the increase is partially due to the decline of population numbers at the Umtamvuna colony. This is also noted at the decline of the Robert’s Farm colony and the Moletjie colony and the increase in the numbers of the Skeerpoort colony. Boshoff also noted a decline in the south-eastern colonies in the commercial farming areas as opposed to the traditional farming areas. One plausible explanation for this and this is one that Hirschauer et al (2020) suggest (and Walter Nesser states in his comments) is that with population declines range contraction occurs and smaller colonies start to disappear. The other possibility that has not been explored and has been noted with several bird species. Landscapes are engineered by humans in different ways across the country and they may be beneficial to a species in one area and detrimental to the same species in another area. As birds and more so probably for wide ranging species like Cape Vultures are easily able to move away to more favorable areas, it may also explain the increases at certain colonies and declines at others. The other important part of the equation that needs to be highlighted is the amount of hard work that numerous passionate conservationists have put into the species and it is also possible that this hard work is now paying off.
    The problem is that not enough colonies are monitored and in some cases those that are monitored, the data is unavailable, or the monitoring is not adequate to provide information on population trends. This is something that needs to be addressed. Despite this and having a look at the data that has been provided both incidental and actual I believe the global population has at least stabilized and that the status change to Vulnerable is warranted.

  7. Red List Team (BirdLife International) says:

    Many thanks to everyone who has contributed to this discussion. We greatly appreciate the time and effort invested by so many people in commenting. The window for consultation is now closed. We will analyse and interpret the new information and post a preliminary decision on this species’s Red List status on this page in early July.

    Thank you once again,
    BirdLife Red List Team

  8. Red List Team (BirdLife International) says:

    Preliminary proposal

    Based on available information, our preliminary proposal for the 2021 Red List would be to adopt the proposed classifications outlined in the initial forum discussion.

    There is now a period for further comments until the final deadline in mid-July, after which the recommended categorisations will be put forward to IUCN.

    The final 2021 Red List categories will be published on the BirdLife and IUCN websites in December 2021, following further checking of information relevant to the assessments by both BirdLife and IUCN.

  9. Warren Goodwin says:

    Agree with and support the proposed classification of ‘Vulnerable’ for this species based on both published and unpublished evidence provided as well as the thorough assessment undertaken by the BirdLife Red List Team.

  10. Warren Goodwin says:

    Further published evidence of stability or even possible increase in the breeding population of this species from colony surveys undertaken in Botswana during 2017 and 2018.

    Goikantswemang, T., Reading, R.P., Maude, G., Selebatso, M., Hancock, P., Borello, W.D., Borello, R.M. and Perkins, J.S. (2021). Breeding Success of Cape Vulture (Gyps coprotheres) At Colonies In the Tswapong Hills, Botswana. J. Raptor Res. 55 (3): 3356. https://doi.org/10.3356/JRR-20-80

  11. Red List Team (BirdLife International) says:

    Recommended categorisation to be put forward to IUCN

    The final categorisation for this species has not changed. Cape Vulture is recommended to be listed as Vulnerable under Criteria A2acde+3cde+4acde; C2a(ii).

    Many thanks for everyone who contributed to the 2021 GTB Forum process. The final 2021 Red List categories will be published on the BirdLife and IUCN websites in December 2021, following further checking of information relevant to the assessments by both BirdLife and IUCN.

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