CATTLE EGRET - MIGRANT OR RESIDENT?

Bird watching in the 21th century took a different turn with many taking to digital bird photography. The old school birder who preferred to identify birds in the conventional way is now bypassed with photo identification. The advantage of having a picture for future reference is very much convenient to a hastily done field sketch. Bird photography today has advocated the need to review and revisit some bird behavior that show unusually high populations during a certain time of the year. Research studies on these aspects have now been undertaken on some commonly occurring bird species by local universities to determine their home ranges and migratory status. The Cattle Egret and the Indian Pond Heron are two such bird species under review.

 Both these species show off nuptial plumage changes of a breeding season with significant color change but no firm nest building behavior is recorded in any known heronry where much photography has emerged. Although it is adjudged a disapprobation to photograph nesting birds and their breeding behavior, the unscrupulous photographer still pursue his habit. There is literature on the breeding behavior and timelines with clutch sizes in old records of G M Henry and others ornithologists of the past but with no firm recordings at present time.

Cattle Egret

The Cattle Egret is of two subspecies. The Eastern Cattle Egret [Bubulcus coromandus] and the Western Cattle Egret [Bubulcus ibis]. The Eastern Cattle Egret; a species of heron is found in the tropics and subtropical warm temperate zones and the Western Cattle Egret is classified as those found outside these areas. Despite the similarities in plumage which is closer to the egrets of the genus Egretta,… they are more closely related to the herons of Ardea.

It is named for its habit in associating with grazing livestock to feed on the invertebrate prey disturbed by the hooves of moving cattle. But today with the shifting of grassland faming to closed house farming systems and overgrazing of grassland we don’t see them associating cattle very much. The cattle egret has a unique adaptation for catching its moving prey in flight …. Unlike most birds adapting to have its head stationary with their eyes focused on its prey, the Cattle Egret moves its head to either side in quick succession before it lunges forward in a stabbing gusto to grab the flying bug. At times it would hitch a ride on the animal’s back picking the ticks and fleas off its hide. There are times when it prefers to relax on the largest terrestrial beast when tired of following it.  

Galoya - Pic Uditha Wijesena

As mentioned above with the foraging livestock moving out and the tall grasses diminishing from overgrazing the Egret is now frequenting the ever increasing urban garbage dumps and landfills for grubs and bugs. Our Sri Lankan domestic garbage being wet and biodegradable is an ideal medium for breeding House Fly [Musca domestica] and the Bluebottle Fly [Protophormia terraenovae.] Both the flies are considered pest and disease transmitting vectors and the Cattle Egret is most welcome on these sites for vector control.

Kurunegala in July 2018 - No Cattle Egrets seen on Garbage

Urban garbage today is a national crisis and the biodegradable component of it is managed by turning it to compost through various programmes. The latest being a Japanese Technology introduced with comprehensive mechanical means to handle over 50 tons of garbage per day. The author is currently in this project on seven sites scattered in the country and is familiar associating the nauseating stench and the hordes of teeming flies swarming all over you in a humid locality. It’s so tricky to avoid them from getting into your garments. And when in the vehicle, its a task that would go on for 20 kilometers or more to rid the last fly out of the car.

This was normal on our site visits until during one visit it was significantly noticed that the flies had all gone. On close inspection it was seen that the flies had now been replaced by thousands of pure white plumage of Cattle Egrets that looked more like white sheets covering the dumps.

Dambulla grubbing alongside Elephants

Ampara - Deegawapi

The reason for the fly less atmosphere was the presence of the Cattle Egrets that feasted on them assisted with  Barn Swallows that crisscrossed the dumps regularly and rest on the roof trusses of the many sheds in these yards.

Barn Swallow - Kurunegala

The presence to the Ban Swallow prompted the beginning of the bird migration period for it being a regular winter visitor to the country……. But then the Cattle Egret? In such heavy numbers to have visited with the Barn Swallow suggests them also to be a group that migrated into the country? This notion had some confirmation with the bird being in all the seven locations in seven provinces at the same time in such large numbers.

Kurunegala February 2019 - Cattle Egrets grubbing inside yards

They initially feasted on the fly population and later picked on the maggots and the fly larvae, ridding the menace of irritation and the health hazard. They are still in the country but will soon be gone if they are migrants. I will keep watch for the increase in the fly population with the Cattle Egret gone in these sites. Their suspected migration was not significant until the number of people getting interested in birds and bird photography increased in the country I feel.

Pollonaruwa

Hambantota

There is scientific research to identify some populations of cattle egrets to be migratory and described as below;
"In many areas populations can be both sedentary and migratory. In the northern hemisphere, migration is from cooler climes to warmer areas. But Cattle Egrets breeding in Australia migrate to cooler Tasmania and New Zealand in the winter and return in the spring. Populations in southern India appear to show local migrations in response to the monsoons. They move north from Kerala after September. During winter, many birds have been seen flying at night with flocks of Indian Pond Herons [Ardeola grayii] on the South-Eastern coast of India, and a winter influx has also been noted in Sri Lanka."

As we have already commenced studies on the Cattle Egret it is high time that a comprehensive study be undertaken on the Indian Pond Heron as well, which also flaunt nuptial plumage sans any breeding noted recently…..there were some unusual flight patterns in large numbers of Indian Pond Herons along the sea coast flying in a Northerly path in and around the Colombo metropolis, observed sometime back.  

Did the Greater Flamingo Leave Bundala Due to Change in Ecology or Otherwise?

Greater Flamingo in Bundala Year 1986                                                        Uditha Wijesena

Sri Lanka is unique in its geographic positioning with regard to World Bird Migration. Breeding birds in the Northern hemisphere migrate to the equatorial regions in the wintery season and back to their breeding grounds in spring and summer. Ornithologist and biologists the world over have studied these bird migratory patterns and developed a set of regular routes called flyways.  Almost always these flyways end up with a landmass beyond which is the southern sea that extended all the way to the South Pole.

Sri Lanka therefore is the last landmass in the Central Asian Flyway. Thus the arid zone in the extreme southern district of Hambantota with the Bundala Wetlands and the  dry zone shrub jungle habitat of the Yala National Park has been a heaven and the last staging post for the migratory birds in the Central Asian Flyway. The concentration of waterfowl in the Bundala wetlands which comprise of three large brackish water-bodies the Bundala, Embilakala and the Malala lagoons were declared a Wetland of International Importance (RAMSAR Site) on 15^th June 1990, and it was the first such to be declared in Sri Lanka and Bundala was the 487 th site in the world. Today Sri Lanka has 6 sites declared as Internationally Important Wetlands listed under RAMSAR.

World Migratory Bird Flyways

The description of Bundala under Sri Lanka and its importance in the listing is cited as follows:

“Southern Province; 6,210 ha; 06°10'N 081°12'E. Flora and Fauna Sanctuary. Four shallow, brackish lagoons and saltpans interconnected by channels with associated marshes, dunes and scrub. It is the most important wintering site in southern Sri Lanka for migratory shorebirds, regularly holding over 15,000 individuals of various species, and provides habitat for rare and threatened water bird species. Human activities include commercial salt extraction, subsistence fishing, wildlife tourism, livestock grazing, and firewood collection. Ramsar site no. 487. Most recent RIS information: 1990.”

Bundala a Protected Area

Bundala records to a very ancient village in the Hambantota District and the famous Assist Government Agent Leonard Woolf’s administrative reports and diaries refer to the fauna and flora and the struggle for existence of its people in a very dry harsh climate. Bundala and its vicinity among the four lagoons however was declared a wildlife sanctuary in December 1969 and remained thus until the area was upgraded to a National Park in January 1993. This brought a stop to all human activity in an area of 2600 hectares requiring relocation of some parts of the ancient village. Later in 2004 it was regazetted with a reduced land area of 3700 hectares and today Bundala is the recipient of numerous other declarations. A “Man and Biosphere Reserve by the UNESCO in 2005 and “Bundala-Wilmanna Sanctuary” in January 2006 identifying a buffer zone of a further 3696 hectares of land adjacent to the National Park.

Though Bundala today is recognized internationally as a final staging post for migratory waterfowl; the actual story of Bundala is but alarming and tragic. If one is to reconsider why Bundala required recognition and protection it could be said without any doubt it was its pristine saline habitat and the wondrous number of waterfowl that frequented the location annually. If it was to be the current condition then Bundala would take time to qualify to a RAMSAR status.

However Bundala was only a sanctuary where the people coexisted with the fauna and flora blending with the sustenance cultivation of paddies in the limited freshwater and with a controlled slash and burn cultivation in the short rainy season from November to January. It was so when it was declared a RAMSAR site in 1990. No human elephant conflicts heard as today and there was never a case where the waterfowl was exploited or disturbed by the villages.

Much earlier to this period it was the occasional trigger happy privileged sportsman who did visit Bundala with a licensed fire arm and a permit from the Government Agent Hambantota to shoot ducks. This habit too ended with the Amendment to the Flora & Fauna Act in 1964. Outside the sportsman it was the genuine nature lover and birdwatcher that did come all the way from Colombo to record the waterfowl and the magnificent Greater Flamingo migration to Bundala. There was hardly a lodging available in the area except for the Government Rest House in Hambantota or Thissamaharama.

Commercialized safaris did take place in a very small way from the early 1970’s with a few jeeps less than 10 in number that operated from Thissamaharama for the foreign tourist who came to visit the Yala National Park. They were then offered a bonus to see the Greater Flamingo in Bundala for an extra paltry sum the jeep driver charged for an extended drive to Bundala via Krinda without any entry fee. These jeep even then were marked as “Flamingo Safari”.

It should be noted that these jeep tours started in Thissamaharama was a substitution to an enterprising personality the famous ‘Tennis Ace’ D. D. N Sevadorai who brought his European and Scandinavian clientele on camping tours to Thissamaharama / Yala in jeeps with all the paraphernalia; tents, cutlery, crockery and even the spotless white table linen all the way from Colombo in the late 60’s and early 70’s. It is ironical to say that it was these humble beginnings of jeep tours that has turned in to a jeep mafia run by the local political goons today. 

National Parks in Sri Lanka   

It is not wrong to say the most Wildlife National Parks in the country have come up not with the sheer interest for wildlife protection or habitat protection but with the greed for the revenue from the entry fees. There was only two National parks the Yala and Wilpattu declared in 1938 until Galoya was declared in 1954. Large scale Development Projects like the Galoya and the Mahavelli Multipurpose Development Schemes did require protected areas for the displaced fauna when large jungle tracts were opened up for settlement.  The 1970’s saw two more National Parks the Yala East and the Udawalawe being declared. The accelerated Mahavelli scheme carved out four National Parks in Maduru Oya, Wasgamuwa, and the Mahavelli Floodplains in Somawathiya. Them being mainly to hold the displaced Elephant population.

Today there are 26 National parks with 15 of them named after Bundala was declared in 1993. It could be clearly said that Bundala, Minneriya and Kaudulla were localities where the tourism trade blossomed and the local hotels in Habarana and Thissamaharama arranged localized jeep safaris to see wild elephants and birds. This triggered off the Department of Wildlife Conservation [DWLC] to fence up ticketing booths and gazette a boundary demarcating a National Park. National Parks are said to be the largest revenue collectors outside the Department of Customs in this country. As recorded by the DWLC the Yala National Park itself has generated Rs. 612 Million as revenue during the period from January 2018 to October 2018.   However it should be noted that these monies all end up in the Government Consolidated Fund and only a meager portion is utilized on the welfare of the fauna and its protection.

Bundala is affected by the KOIS Project

The upgrading of Bundala to a National Park in 1993 could be viewed only as a significance to it being declared a RAMSAR site in 1990 or as said before the revenue from entry permits from an already established localized wildlife tour operation. It is noted that most RAMSAR sites the world over are not strict reserves but where human activity coexist with a faunal presence. That was basically how Bundala became a RAMSAR site with its abundance of waterfowl until about 1989-90 when trouble started.

The then political ideology to open up large scale development projects primarily for political stability required a similar project as the Accelerated Mahavelli Scheme in the North Central Sri Lanka in the South as well. This was also highlight in a Commission Report on the 1971 youth unrest and the insurgency that originated in the South. The result being the Kirindi Oya Irrigation and Settlement Project [KOISP], or better known as the Lunugamwehera Reservoir project. The proposed KOISP Right Bank Canal [RBC] was to extend all the way to the Badagiriya Tank the then existent last paddy tract on the Malala Ara basin.   

The KOISP performed below expectations with the expected water yields not achieved and messing up cropping patterns. It is rumored of a mix up of flood records where isolated heavy flooded years being considered for yield calculations when they should have been left out as outliers. The Right Bank Canal [RBC] planned to feed the Badagiriya Tank had to stop short of the Badagiriya Tank and the Tracks 3 & 4 located just above the Bundala Lagoon be abandoned due to the water deficiency.

The feasibility report on the KOISP did say that the land was not the best suited for paddy but for other fiber crops. The political administration and the settlers were adamant to develop the land for paddy with the misconception that the already existent 5 tank irrigation scheme in the lower areas with alluvial soils did give favorable yields. Today people have started moving to highland crops as banana and gherkin instead. 

The drainage water from Tracks 1, 2, 5 & 6 were confined above the A2 road trace from Hambantota to Weerawila and are flowing into the Embilakala and the Malala Lagoons. The salinity in both these waterbodies dropped with the swelling water levels. The favored brackish water for the aquatic organism diminished bringing a total change in the ecology. This high water level in the Malala Lagoon was controlled to a certain aspect by providing a permanent opening into the sea through an outfall canal and groyne constructed into the sea.   

A performance audit report compiled in the year 2000 for the KOISP refers to the environment in a very short paragraph thus ….

“The environmental record is mixed with some significant disbenefits, notably a reduction in salinity of the ecologically valuable coastal lagoons. However, the human environment within the command area is now aesthetically attractive compared to adjoining slash and burn agricultural areas, while malaria incidence is reported to have fallen significantly.”

Even though the effects of excessive drainage is seen only in the Embilakala and the Malala Lagoons it is strange to note an ecological effect on the Bundala Lagoon as well even though Bundala is located slightly higher in a different catchment. It would have been of the same fate had the tracks 3 & 4 being opened for paddies which would have drained directly into the Bundala Lagoon.

  

The mystery behind the Bundala Flamingo and change in Ecology    

Bundala had but a flagship species the Flamingo. Of all the issues that Bundala faces today from human activity within the park to the invasive flora of Prosopis Julifora, commonly known as ‘Kalapu Andara’ in and around the wetland it is the missing Greater Flamingo that is to be of significance to everyone.

Flamingos are all members of the Phoenicopteridae bird family and are six species; American (Caribbean) Flamingo (Phoenicopterus ruber), Andean Flamingo (Phoenicoparrus andinus), Chilean Flamingo (Phoenicopterus chilensis), Greater Flamingo (Phoenicopterus roseus), Lesser Flamingo (Phoeniconaias minor), Puna (James's) Flamingo (Phoenicoparrus jamesi). Of the six species Lesser Flamingo is the most numerous followed by the Greater Flamingo. The other four species are confined to the new world in the Americas. Sri Lanka is frequented by the Greater Flamingo a winter migrant from the Indian Rann of Kutch, a salt marsh in the Thar Desert in the Kutch District of Gujarat.

Pic Courtesy: https://birdeden.com/what-do-flamingos-eat

The greater flamingo is the largest flamingo species and can measure up to five feet tall when standing erect with its head raised, but only weighs a maximum of eight pounds. The lesser flamingo is the smallest flamingo reaching three feet and typically weighs 3-6 pounds. The flamingo's most characteristic habitats are large alkaline or saline lakes or estuarine lagoons that usually lack vegetation. These water bodies could be far inland or near the sea. All flamingos feed holding their bent bills upside down for several hours a day, filtering out food while skimming the water. They may seem to nibble or scoop at the surface of the water as they strain out small bits of algae, plant material, insects, brine shrimp, and other foods that make up their omnivorous diet.

Flamingos are said to be monogamous and lay only a single egg each year. If the egg fails to hatch or is predated they do not lay a replacement and can take several years to recover their population. However in the year 1997, a photograph published in a local newspaper of the Bundala flamingos’ nest-mounds did arouse interest among the bird enthusiasts. They never did lay and this development was thought to be an instinctive practice before returning to their customary breeding grounds.

It is noted that all this activity related to the Bundala flamingo came to an end in the mid-nineties.  There had been consecutive dry years where the lagoon was almost dry and ever since the drainage water came into the lagoons the alkaline ecology was affected.  In return the Asian Development Bank which was the funding agency for the KOISP did take up the task in analyzing and researching as to what went wrong in Bundala. But it was always with the focus of the quality of the discharge water and its biological acceptability as a discharge into surface waterbodies.

It is speculated that the Bundala lagoon has had no direct effect of the KOISP drainage discharge in to the lagoon as the tracts 3 & 4 are abandoned and therefore the reason for the missing Flamingo is not directly related to drainage discharges. There are other thoughts as well, when the saltern was made to stop letting brine water enter the lagoon which in return affected the artemia cysts growth the preferred food of the Greater Flamingo.

However as of present there has been no research done to ascertain the reason for the Flamingo to abandon Bundala and on a broader sense the whole of South and South/Eastern Sri Lanka. The Flamingo then was not confined to Bundala but did frequent all the southern salterns; the Maha lewaya in the Hambantota town and even the Karagan Lewaya which today has been converted into an inland harbor. They did frequent the Palatupane Lewaya in the immediate outskirts of the Yala National Park entrance.

However it should be noted that the flamingo is highly dependent on diet which is only found in abundance in highly alkaline concentrated water bodies and the change in the ecology does affect their survival drastically.

There had been similar incidents elsewhere.  The Lesser Flamingo is flying off, and fleeing a seemingly shrinking Lake Nakuru, the home that has sheltered them for uncounted centuries in the Lake Nakuru National Park in Kenya. The lake is drying and the receding shoreline result for many hundreds of dead flamingos littering the caked lakebed. The catchment area around Nakuru has been heavily deforested, and its rivers are running dry. Years of drought have further reduced the water supply. Global temperatures are rising and local sewer and industrial runoff from nearby Nakuru town is polluting the lake. This shallow lake and its shrinking flamingo population remains a complex question. The simplest answer is but its favoured food the blue-green algae has diminished within the lake and is no longer produced in that habitat ….again a change in the ecology.

Therefore we can draw similarities of Lake Nakuru with Bundala. The only difference being that the Lesser Flamingo of Lake Nakuru was a breeding resident while our Greater Flamingo is a migrant from the Rann of Kutch.  However they are quite in abundance in the Northern peninsular, the Mannar salterns and other alkaline lagoons and shallow seas around. But for the Greater Flamingo to abandon the South and the South/Eastern Sri Lanka is not really an issue related to the ecological change that Bundala underwent as a result of the KOISP.

So let’s be optimistic that they would come back someday once things are favorable for them or until the reasons for the loss of its favoured food source in the southern saltpans are found out through a comprehensive study.