A farmer (called Banda) in Wasgamuwa one day told me” I really want to kill all the parakeets in Wasgamuwa ” frustratingly and angrily. I immediately understood this serious consideration of him. Banda grows Sesame (Thala in Sinhala) in his chena during the dry season and he has got some Sesame fields presently in his Chena.
Sesame is an ideal crop to grow in the dry season in areas like Wasgamuwa as it needs very little water. Farmers still grow sesame like in the past without using any fertilizers or pesticides. There is a good demand for good quality sesame in Sri Lanka.
The Rose-ringed Parakeets (Psittacula kramerii) are the parakeets that he wanted to kill because they devoured his mature sesame plants. In the region where Rose-ringed parakeets are native, it has been identified and classified as a serious avian pest to agricultural and horticultural crops. So I decided to observe Rose-ringed Parakeet’s foraging behaviour in Banda’s chena.
Rose-ringed Parakeets (here after referred to as parakeets) flew into chena in small groups of approximately 25 birds, especially in the early morning and in the afternoon. On arrival, they perched on a nearby tree before landing on the Sesame plants. This was to check the area first for any human presence around the chena. After observing the area carefully they landed on the Sesame plants. By using the strong beak, the muscular tongue, and the flexible feet, they collected the Sesame seeds very effectively from the pods that other birds find difficult to do.
After landing on a Sesame plant they started searching for mature Sesame pods. They climbed and moved across the plants in search of mature pods. They were after seeds inside the mature pods. The zygodactylous foot pattern (arrangement of two forward and two backward toes) of the parakeet is well suited for climbing, moving sideways, and for all other acrobatic movements.
Damage to the Sesame plants was caused by the landing and the searching action. Initial heavy landing on branches made branches bend and later break off. They moved from one branch to other regularly searching for mature sesame pods with mature sesame seeds. When they were searching, they used their bills to hook on to branches. This hooking damaged the stems and the branches.
After finding a mature pod, most of the time they did cut the pods off the stem. I observed two different ways of obtaining the seeds from the pods. One method was, they held the pod with a foot and opened the pod by using the beak and slowly extracting some seeds from the beak. When they extracted the seeds from the pod they looked very messy as a lot of seeds got glued onto the outer side of the beak. The other method was, they kept the pod in the beak and opened it partially, and then moved the pod laterally in the beak nibbling the seeds. For this method, they did not use the feet at all and after getting some seeds they just dropped the pods.
Sometimes they did not cut off the seed pod from the stem, instead they cracked the pod and removed one half of the seed pod to reach the seeds whilst the pod was still attached to the plant. I think this is a wasteful feeding method by them as most of the time they just discarded one half of the seed pod and also they didn’t eat the rest completely.
At times they took a part of Sesame branch with 10 -15 pods to a nearby tree and leisurely ate the seeds while holding the branch with a foot. I also observed them taking one seed pod to a nearby tree and eating it leisurely. Taking a branch or a seed pod to a tree was not very commonly observed.
Even though parakeets do not feed randomly, sometimes they damaged immature seed pods as well. When they did it, they just cracked the seed pod and ate only a few seeds. Siriya was angrier about this, and he said ” Why the hell is that they don’t eat the whole thing, just eat the damn thing completely”.
Banda and other Sesame farmers in the area used catapults to chase them away. As the parakeets are very quiet feeders, the farmers normally don’t know about their presence in the Sesame fields. Farmers generally do not guard Sesame fields against birds like they do with the paddy fields. But like Siriya all the Sesame farmers that I spoke to were very concerned about the damage done by the parakeets.
I did not make any attempt to quantify the damage. Hence I don’t know how significant is their damage to Siriya’s Sesame harvest. It is clear that we need more research on this subject to learn more about this problem and to manage this problem effectively. Apart from the study done by Professor Kotagama on parakeet’s damage to paddy, we haven’t done any scientific study on any avian agricultural pest. So I think it is time for us to put our effort to it. this subject. Definitely, I am going for it!
