Veterinary Work on White-Backed Vultures in Pakistan
Lindsay Oaks— 17 April 2001 — in Asian Vulture Crisis    Share

Lindsay Oaks, DVM, PhD, Dip. ACVM is an assistant professor in the Department of Veterinary Microbiology and Pathology at Washington State University, Pullman, Washington. He is a long-time friend and collaborator of The Peregrine Fund’s, and an expert on avian viral diseases. When early studies on dying vultures in India suggested that an infectious, possibly viral, disease might be responsible for the mortality causing the population crash, The Peregrine Fund asked Lindsay to develop and coordinate a worldwide team of laboratories and experts to identify the disease agent as quickly as possible.

Of his first field trip to Pakistan, Lindsay wrote……..

In November 2000 I traveled to Pakistan on behalf of The Peregrine Fund to determine if an infectious disease was affecting White-Backed Vultures (Gyps bengalensis) in Pakistan which could possibly lead to a population decline as is being reported in India. It was my first trip to Pakistan, and my first opportunity to observe old-world vultures in their natural setting. I arrived in Lahore late in the evening, and was met by my colleagues Dr. Munir Virani from Kenya and Dr. Pat Benson from South Africa who took me to the hotel for some badly-needed rest after a very long trip. As part of my supplies, I was carrying as baggage a "dry shipper," a container with liquid nitrogen needed to store and transport samples back to my laboratory. While this particular container is allowed on aircraft, liquid nitrogen, in general, is not, and despite endless pre-arrangements and notification (and clearance) by all the involved airlines it was still yanked off my flight in London as "dangerous cargo." I had planned to lay over in Dubai to rest up and visit old friends, but instead it turned into a marathon event in trying to recover "dangerous cargo" and ensure that it made it to Lahore when I did. Fortunately, this was ultimately successful, and I had learned much more about the cargo business than I ever wanted to know. Of course, I was then accosted by Pakistan customs, which entailed another series of very long and eventually successful negotiations to bring these supplies into the country!

The next morning, we did not have to go far to find our first vultures. There is a substantial urban population of vultures right in the city of Lahore. The colony we visited was in a large park called Lawrence Gardens. Here, many of the trees had groups of two to four vultures sunning themselves in their treetop roosts. Many of the larger trees had nests in various stages of construction, and in some birds were already incubating eggs. Of course, these vultures were completely habituated to people, and so we were able to observe at very close range these impressive raptors. I was a bit disappointed in that I previously had visions of finding these birds in the remote corners of Pakistan, whereas the only adventure to this point was to not trip over the picnickers while staring up in the trees. We did not find any sick or dead birds here, and interviews with the groundskeepers (thanks to Munir’s fluency in Urdu) did not suggest that they had noted anything unusual in the recent past.

So the next day we headed for the field proper. The Indus plains in the Punjab province are all very, very flat and bounded by the five major rivers of the region ("Punjab" means "five rivers"). An extensive series of river-size canals interconnects these rivers and provides the extensive irrigation that has converted the region from desert to a rich agricultural area that grows cotton, maize, mangoes, citrus, and a variety of other fruits and vegetables. Our first destination was a forest plantation outside the town of Changa Manga (named for two notorious bandits that roamed the region in the days of the British Empire, and are now regarded as folk heroes) – the British many years ago planted hardwood trees as a source of timber, which are now mature forests and carefully managed by the Pakistanis. These large trees provide nesting and roosting habitat for the vultures, and the plantation at Changa Manga had many vultures. We arrived early in the morning so that we could observe the birds at roost, and hopefully find some sick vultures. The birds at this time of day were sunning themselves, preening, and also nest building. It was interesting watching the birds select proper nesting material, which clearly was held to very stringent specifications and was selected very carefully. A vulture would fly to a tree and after considerable evaluation, which included breaking off and discarding any number of unsuitable branches, one was finally found that was just right and was carried back to the nest-in-progress.

We did find several dead vultures at Changa Manga, and although these were already dead for at least some days and not ideal samples, we were able to collect some useful specimens. From a preliminary examination, the cause of death was not evident and a diagnosis would have to await some laboratory analysis.

Later, as the day warmed up and thermals began to form, the vultures began soaring, rising up, and eventually dispersing in their daily search for food. One of the most memorable experiences of the whole trip was watching entire vulture colonies, which may be many hundreds of birds, all rising up together and out of sight in a giant column of soaring, circling birds. Another very memorable experience from Changa Manga was fruit bats. At home here in the USA, bats to me are small creatures about the size of a mouse – fruit bats on the other hand are enormous, and it is a very impressive sight to see hundreds of these Red-tailed Hawk-sized bats flying around your head!

From Changa Manga we then returned to Lahore, and over the next few days had a series of meetings to arrange logistics, permits, and supplies. Then we headed to Multan and Dera Ghazi Khan in central Punjab, some six to eight hours drive southwest of Lahore. In these areas, vulture colonies are found in Sheesham trees (Dalbergia sissoo), another hardwood that is planted along the banks of the canals both as a source of timber and to stabilize the banks. It seemed that anyplace where there were groves of Sheesham trees there were also colonies of vultures. We found a number of dead adult vultures, many of which had no grossly apparent cause of death, and from these birds samples were collected for later analysis once I returned to the USA. However, despite these unusual deaths, there still appeared to be large populations of vultures at the sites we visited.

One aspect of the trip that cannot be ignored is the courtesy and hospitality of the Pakistanis. Although you hear many scary things in the media about this part of the world, the greatest danger we experienced on this trip was being drowned in tea and smothered in food. It seemed that there is no purchase made or any business conducted, no matter how small, without tea and biscuits (cookies). Over the next few weeks, we spent many days on the road traveling throughout the Punjab in search of sick vultures. We saw many vulture colonies, some dead vultures to collect samples from, and were always welcomed even if we were considered a bit odd due to our interest in vultures! The only scary experience was the driving, which could only be described as completely ad lib with regards to rules. Traffic congestion in town prevented building up enough speed to be worrisome. However, on the open roads this was another matter, and "open" meant few enough other cars, trucks, buses, bicycles, motorbikes, rickshaws, pedestrians, livestock with and without carts, etc. to not prevent attaining speeds at which collision with any or all of the previous seemed inevitable. Driving the open road at night was truly memorable for an American used to orderly traffic flow!

Fortunately, no accidents occurred, and eventually we returned to Lahore, organized all the samples that had been collected, and my trip was over. But the work continues there, and my real diagnostic work at home is only now beginning to try and determine what is killing the vultures in Pakistan, India, and other parts of Asia.

This is a fascinating – and alarming! – turn of events in the life of vultures in Asia, and I am pleased to be a part of The Peregrine Fund’s remarkable effort to understand the cause of the vulture population crash as the first step towards helping ensure their survival as a species.

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