The lakes a year ago and at present. Photos: Monwar Hossain Tuhin/JU teacher & Palash Khan/The Daily Star
The number of guest birds coming every year to Jahangirnagar University (JU) lakes since the eighties has been falling for the last few years in such a way that last year there was no “bird fair” held as part of the campus’s recent trend.
Observers say it happened mainly due to aquaculture or fish farming in the lakes, human invasion or poaching, new establishments near the waterbodies and noise pollution.
A few years ago, thousands of foreign birds of around 20-30 species and several of the local birds used to start flocking at JU in August-September and leave in March-April. But things have changed of late, as they have started to find alternatives to the Green JU obviously because of public interference of their inhabiting and breeding areas, and lack of food including aqua vegetation and insects in the waters.
Because of the number of birds staying on the campus it experienced more and more people coming to enjoy the birds’ beauty.
Experiencing the popularity, zoology department and environmentalists jointly in 2003 launched a bird fair when bird watching with binoculars and telescopes, art and quiz competition for school students, discussions, photography exhibitions used to take place.
But, last year, there were no birds and therefore, no festivity.
The birds used to stay and breed mainly on two lakes situated near and behind the registrar building. These were declared sanctuary for birds in 2005 and aquaculture was banned to ensure safe-haven for the migratory birds. The administration too gave its earnest attention to the tourism aspect of the issue, and gradually developed the lakeside, walkway and put sitting arrangements on the banks.
Barbed fences were also erected and information stickers posted around the lake to prevent people from going close to the birds that makes the birds fly away.
Fish farming, however, has not been prevented at the other seven lakes and ponds; those are leased for commercial farming over three-year contracts. Mostly the staff and the teachers are the lessee. The administration last year also leased a 14-acre area, which was rich in medicinal plants and birds and butterflies, for producing turmeric.
When there were no birds seen last winter, students, teachers and journalists blamed the present administration for their frustration, saying that indiscriminate fish farming in the lakes had driven the birds away. They claim that the time when lime was used in the lakes for routine cleaning was wrong. Moreover, removal of the lotus and lily beds, water hyacinths and other green vegetation was another major reason behind the lakes being bird-forsaken.
The administration since has been facing serious criticism on the campus and in media for such unfriendly behaviour against ecology and biodiversity.
Lime is used before releasing baby fish to prepare the water body as favourable for their growth.
As approached by the writer to find the concrete reason behind the upset, the authorities denied that they were wrong in putting lime last year that could hinder the birds from coming to the campus.
“We used lime as usual last April or May. Fisheries officials from Savar came and administered the process and quantum of baby fish was released there,” defends Deputy Registrar (estate) ABM Azizur Rahman, who is also a member of the campus’s internal resources committee.
That was not commercial farming. The administration usually releases some baby fish this way and brings them up for selling after two or three years, he said.
Prof Abdus Salam, another member of the committee and teacher at zoology department, could not confirm any major reason behind the migratory birds’ not coming last winter. He argues that the number of birds from the cold regions this time was low not only at JU but also at different parts of the country.
He cited similar fall in number of migratory birds in Dinajpur, Nilphamari and Chittagong, but confirmed that the serene haors of Sirajganj and Sunamganj had experienced thousands of guest birds.
According to his observation, the lakes were getting unfavourable for any water species to live. That is why, those needed to be refurbished as their beds turned pollution affected and too muddy. “We had to neutralise the water with lime after the birds were gone,” he said.
The lakes are generally cleaned after the birds leave in March-April. But another zoology department teacher contradicted the administration, claiming that lime was used in December 2011, which was the major reason behind the upset.
According to Prof. Monwar Hossain Tuhin, also known as a butterfly expert, a possible weather change in the cold regions and thus availability of foods for the birds in winter “may be the reason why the number of birds has been falling for the last few years.”
Weather in the cold regions might be getting warmer, and thus those birds got favourable condition to cope with and find foods, he says.
“But the birds which came in November-December 2011 found an unfavourable situation as the lakes were too clean for them with lime and increased toxicity, he observes.
Most of the migratory birds use leaves of aqua plants floating on water as breeding cover and find the vegetation and small fishes as foods. They also like to camouflage with the help of those leaves sensing presence of adversaries, he adds.
The administration should be more careful in dealing with the dynamic biodiversity of this campus, Prof Monwar suggests.
Early February last year, the birds’ festival took place for the last time. VC Shariff Enamul Kabir inaugurating the fair said a safe zone for birds must be there on the campus. “The number of birds in Bangladesh is decreasing day by day. We need to do something immediately to preserve them,” said the VC (The Daily Star, February 5).
Prof Salam admits that had there been water hyacinths and lotus in the lakes last year, the birds might have come. The measurement of lime might not have been correct, he suspects.
With a view to ensuring the travel of guest birds to the campus in the upcoming winter, the administration in June will plant lotus in the lakes to increase vegetation, he assures.