Conservation

BLSA POSITION STATEMENT ON PIED CROWS

Posted on the 17th September 2012

The increase in the abundance of Pied Crows in the Western Cape and the potential threat they may represent to other indigenous bird species and biodversity in general has been raised at Forum level. Certain websites have been coming to the fore in recent months advertising services to kill Pied Crows and other perceived "problem" predators and there is a concern that some farmers may be using poison.

BirdLife South Africa is not in in favour of this approach and does not support the uncontrolled killing of Pied Crows or other indigenous wildlife. It holds to the principle that sound scientifc research is needed to determine the level of threat before control programmes can be considered. The Pied Crow issue will be taken forward as a student project at the Fitz.

Below is BLSA's position statement on Pied Crows.

Position statement on the potential impact of an increased abundance of Pied Crows Corvus albus on South African biodiversity

BirdLife South Africa (BLSA) recognises the potential threat of an increasing abundance of Pied Crows Corvus albus on other indigenous bird species as well as reptiles, amphibians and mammals.

In acknowledging this threat to biodiversity BirdLife South Africa supports the need for urgent scientific research to better understand and quantify the degree of this threat on our indigenous bird species.

These potential threats could include;

- Impacts on reproductive success of threatened raptor species due to competition for prey, mobbing raptors during hunting and direct mortality of nestlings and fledglings.

-  Impacts on smaller passerine species through increased mortality rates and reduced reproductive success due to predation on adult and juvenile birds and eggs.

 

-  Impacts on other components of biodiversity, including increased predation levels on small reptiles such as tortoises and lizards, small mammals and amphibians, at elevated natural predation levels.

These potential threats are based on many anecdotal reports across the country and increased sightings and frequent reports of Pied Crows engaged in the abovementioned behaviours. However, careful investigation of how humans have influenced the expansion of both the crows range and their numbers needs to be conducted to best evaluate the causes of these potential problems and develop solutions.

Other indigenous Corvid species, the White-necked Raven Corvus albicollis and Cape Crow Corvus capensis are also perceived to impact on indigenous biodiversity through natural predation, however anthropogenic land transformation and climate change can rapidly alter ecological communities leading to increased impacts by different Corvid species. There has been documented range expansion in the Cape Crow and this also requires scientific research to document the rate and scale of expansion and potential impacts resulting from expansion.

BirdLife South Africa does not support the control or poisoning of indigenous Corvid species in any manner whatsoever.

BirdLife South Africa reserves action on this issue until adequate scientific evidence demonstrates the need for appropriate action for threatened species and a full and balanced appraisal of this perceived threat has been completed.

 


COMMENTS

368
CHRIS CARVER-BROWN (posted: 2016-08-14 12:07:16)
I recently moved up to the Zambian Copperbelt and I am stunned at the number of Pied Crows in all the urban areas. I can only put this down to the PC intelligence and their adaptability to messy humans. Sadly a lot of other indigenous birds that I remember from my years growing up here seem to have either moved off or been eradicated by the Pied Crows. Hopefully some modern science can help us address this?
SHAUN MILES (posted: 2013-09-02 02:41:49)
Pied Crows are killing my Sheep and Lambs. They just peck the eyes out or eat the ears off, most do not make it. In August month I have lost 14 Sheep and 7 lambs. Have 4 sheep that are alive that have only one eye. It is over R 20 000 I have lost. Any one got a way to stop it please let me know.
PROF. LES UNDERHILL (posted: 2012-09-22)
Hi Team CapeBirdNet,
Early this year, one of the news items on the
SABAP2 website was about Pied Crows. It is archived at

http://sabap2.adu.org.za/news.php?id=2327

In a nutshell, in the eastern and northern parts of the region, there appear to have been mostly decreases, with some large decreases in the Free State. In the southern and western parts, there have been increases. The full detail is in the news item.
Les
KEN WYNN-DYKE (posted: 2012-09-18)

Hi
About 8 years ago we lived in Durbanville and about a block away from our house was a primary school. We could hear the school bell ringing so I got used to knowing when their breaks occurred. If I went outside and looked into the sky above the school just after the end of a break there were often many crows circling overhead. On one occasion I counted over fifty. It seemed to me that they waited for the children to return to their classrooms and then swooped down to pick up the scraps of food left behind. Someone else mentioned the number of crows at squatter camps and rubbish tips. They are very intelligent birds and will find all sorts of easy food sources.
I now live in Helderberg Village and we have a pair of Spotted Eagle Owls which have nested in the fork of a large pine tree for many years. Suddenly about three years ago the Egyptian Geese took over the nest spot but every time they lay the crows watch and as soon as the nest is unoccupied the crows swoop in and take the eggs out of the nest. This has happened twice in the last three months and now they are trying to lay again.
Regards
Ken Wynne-Dyke


KIM WRIGHT (posted: 2012-09-18)

Hi All
I do not believe that eradicating the crows is the solution to the problem. Pied Crows are indigenous and we have to keep that in mind. Yes, they do annoy the raptors at times, and yes, there are quite a lot of them around, but why do people always want to rush out and solve the problem by killing things? We have mosquitoes and other insects that can be a nuisance at times, but we learn to live with them and I do believe that many raptors have learnt to deal with the presence of crows in their environment.
There is no doubt that the number of people living close to natural areas has increased the amount of food available to this species, but I also get the impression from the remarks I hear repeatedly that baboons and crows are in the same category. They are seen by many as an irritation and something that can be “sorted out”. It is not that easy. The baboons were here before us and so were the crows, so eliminating them is not the solution.
We have to learn to live with them. They are part of the natural world and have as much right to be here as we do. They are really not as bad as people are making out.
Kim Wright


DALE WRIGHT (posted: 2012-09-17)
Dear All,
I’m glad to see that BirdLife South Africa’s position statement on this issue has generated some good debate.
Before any management intervention is developed for this perceived threat we do need sound scientific evidence of the extent of the problem. We have strong ornithological research institutes in South Africa and it is up to them, and ourselves (BLSA) to drive the search for answers.
Let us not forget how frequently humans “manage” natural problems they have created, with further negative consequences (rats and cats on islands springs to mind?!).
Further, we are discussing an indigenous species, thus the principle is perhaps larger than the single species (Pied Crow) issue itself, if we are to advocate “managing/eradicating” indigenous species where could that road end? Cape Sugarbirds are sometimes problem for Flower Growers---would this require management?
This is why sound science is needed. And fortunately we have word that some institutions may be taking up this banner, thus hopefully we will have evidence to act on in the not too distant future.
We (Ornithological community) are not ignoring this potential problem (we have all heard and seen evidence of this problem for ourselves), we are approaching it in a structured, professional manner to ensure the best long-term outcome.
Kind regards,
Dale

LUCIA RODRIQUES (posted: 2012-09-17)
Hi Dusty,\r\nI am finding it difficult to put your reply into the context of my email.\r\nWho is the messenger and how do you get that he/she is being shot?\r\nSeems we are proposing the same thing; look at how we are managing the environment and do things differently.\r\nOne thing I forgot to add, is that during my discussion with the farmer re the injured JB, he admitted that the Pied Crows are particularly bad during the weeks he has teams of workers in the field tending to the orchards and vineyards. The crows scavenge off the debris they leave behind after their meals.\r\nKind regards, Lucia.\r\n\r\n
TONY REBELO (posted: 2012-09-17)
The issue is: what is the problem? It is the Crows, or what is allowing the Crows to increase? If the Crows are not the problem, then how is killing Crows going to solve the problem? In fact, it might very well make the problem worse - we might be killing the best solution to the problem we have created!
It is not a matter of fiddling while Rome burns. The appropriate analogy is destroying all fiddles because Rome is burning! How does that solve the problem?
Ta
Tony

DUSTY (posted: 2012-09-17)
Hi All,
Don’t shoot the messenger. Don’t worry that our managing of the environment has allowed certain species to bloom into vacuums we have created. If we sit and do nothing perhaps we will be overrun with Pied Crows and Cats. I seem to remember something about Rome burning whilst someone fiddled. If numbers are excessive what is wrong with looking at managing a problem we created. I agree however that Poison is very non selective and is not my tool of choice.
Regards
EDusty

LUCIA RODRIQUES (posted: 2012-09-17)
Dear all,
To add a footnote to the Pied Crow discussion. A season or two ago, Dirk Havenga, Langebaan resident and guardian of the Black Eagle pair at the quarry, described to me a credible sequence of events that led to a pestering Pied Crow being caught mid air by the female Black Eagle, killed (obviously) and taken onto the nest to feed the chick. I have also noticed this season, (as has Rob Simmons) that the SM Black Eagle pair are seriously getting their own back on the Pied Crows that mob them at their nest cliff. I feel it is only a matter of time before they start catching them. Also about two years ago, I was watching the SM pair hunt near Scarborough. They caught a dassie and then flew back towards NH Peak with it. The female flying low carrying the prey and the male higher up, fending off about half a dozen Pied Crows. What fascinated me was that at a certain distance from the Scarborough area, all the Pied Crows turned in unison, and flew back towards Scarborough. It seemed as though they were harassing the Beagles out of their territory. Therefore I must say, that in my experience, Pied Crows are not getting the upper hand of Black Eagles. But having said that, Kevin Drummond Haye, recently witnessed Pied Crows taking the prey away from an almost adult Black Eagle (4 years old). But then she is a floater, and in my opinion they are more vulnerable to this sort of thing. Finally, I don’t think all raptors are as fortunate. At the beginning of this year, I was on the slopes of the Helderberg, chatting to a farmer. He told me of a Jackal Buzzard being driven onto the ground by Pied Crows. He chased them off and took the injured JB to Eagle Encounters at Spier. They healed it, but it is not releasable and has now become one of their educational birds.
And a footnote, to the footnote; I have two pairs of Beagles that regularly catch Egyptian Geese and another very recent record of a Black Eagle being disturbed at the carcass of a recently caught Egyptian Goose, in the Cederberg, no less!So what I am saying is that I also agree with BLSA and Tony that we should not go all out to rid ourselves of Pied Crows.( and EGeese) We must look at why they are so numerous and alter human habits.
Kind regards, Lucia.

TONY REBELO (posted: 2012-09-17)
Hooray for Birdlife ZA.
The standard human knee-jerk reaction to any problem: kill it! (unless its human, in which case race, creed and religion need to be assessed first).The point is that we don’t know if Crows are a problem, or just a symptom. Often is easier to kill the messenger than to try and work out what the situation actually is.
I think it is crucial to ascertain what exactly the problem is. Otherwise the service that crows may be providing to the situation arising may be replaced by a less attractive or amenable alternative. Or worse, we might overlook something important that we should be alerted to. Lets first find out what is broken before we start fixing it.
Good to see that Birdlife has advocated discovering what this indicator species is alerting us to! Let us hope that the cause is reversible and not another unrestorable trajectory that humankind has sent itself upon.
Ta
Tony