Glimpse of Hoskote lake

Wetland, as the name says the land that is wet.

So every land that is wet is a wetland ? You may ask.

Well! not exactly, the land should have soil on it.

Can we consider the water over a piece of soil on the side of the road that we see especially after a heavy downpour?

Umm... no, that does not count either because there is no vegetation in or around it.

To define a wetland one needs to observe if the soil is covered with water either permanently or seasonally along with a vegetation and animal life in or around it. Clearly, it means that Antarctica is the only continent that does not have any wetland.

Technically those are the key factors that determine the wetland and if you look closely towards its vegetation you can determine the type of wetland that you are seeing in front of you. Along with vegetation, the source of water also varies with each type of wetland.

By the way, can lakes be considered as wetlands? I am not 100% sure on this although many definitions overlap and incline towards telling that a lake is a wetland. However, I do not think lakes have hydric soils (soil that form due to lack of oxygen when water stays for a longer duration) beneath them or have vegetation through them. However, the areas surrounding lakes definitely qualify as wetlands because either marsh or swamps are usually seen on their shores.

We can go talking about different aspects of wetlands but for now let us explore by taking one such lake which has marsh around its shore, Hoskote Lake in rural Bengaluru.

This lake is a significant water body surrounded with different types of habitats such as marsh, grassland and shrubs. As you walk on the road you will be greeted with songs from abundant avian friends. Around 266 different species of birds (according to the data from eBird) had considered this lake and its surroundings as their home either permanently or for a shorter period of time when they migrate from long distances. Two-sixty-six, with that number on her heart, the place smiles and tells you about the diversity of birds found here.

Some of the gorgeous guests that visit in and around this wetland include - Northern Shoveler, Northern Pintail, Black-tailed gotwit, Bluethroat, Western Marsh Harrier etc.

In this essay I explore different components attached to survival of the lake. This is one of the few places I used to visit often for photographing birds. First time I had visited Hoskote lake was in 2016 and for the next three years my visit was mainly during winters. When I first visited this lake the view of the construction work was distant but concrete had crawled its way towards the lake eventually. Then there was a familiar sight everywhere, plastics and other garbage. I feel there is an urgent need to not only clear the garbage but also find a way to protect the boundaries of the lake.

An Openbill Stork against the backdrop of a marsh followed by a small forest patch. The marsh is home to many wetland birds, a little cormorant sitting below right of the stork.

Northern Shoveler, one of the migratory birds that often visits in the lake during winters.

Another visitor, Little Ringed Plover, which migrates within India and few come from outside to winter in the sub continent.

On my first glance it looked like majority of the birds are actually increasing but when looking closely numbers have only increased from previous year. Understandably the one of the reasons for the dip from 2020-22 is due to records of these birds might not have taken due covid pandemic.

Hence I was comparing the data of 2024 with the year, 2019. On a positive side I see the numbers of every bird in the list are higher than the one from 2019, except Osprey.

Image taken from Google Earth Pro represents the scenario of Hoskote lake and its surroundings in December, 1985.

Image taken from Google Earth Pro represents the scenario of Hoskote lake and its surroundings in December, 2014.

Image taken from Google Earth Pro represents the scenario of Hoskote lake and its surroundings in December, 2024.

White wagtail which specialists in wetland habitat migrates within India during winter.

White-cheeked Barbet, an endemic to the Western Ghats is also seen around the Hoskote lake.

Data source and Acknowledgements:

• The dataset (1990 to December, 2024) of birds was downloaded from eBird.

• GIS images were created from Google Earth Pro.

• A big thanks to Canopy collective for providing the toolkit for conservation. It made connecting all components a bit easier for me.

Let us talk more about birds shall we? Below is the trend for some of the birds starting with raptors.

Above graph describes trend of raptors found in the lake from various periods. On the x-axis, you can see the years and on the y-axis, the number represents the count of the birds during this period.

I find similar patterns in the graphs of migrant birds such as the numbers of Brown Shrike, Gray Wagtail, Black-tailed Gotwit and Green Sandpiper have gone beyond what it was in 2019. While I am not sure why the count of Bluethroat and Garganey did not go up even though they are insectivorous as others in the list. I can only imagine reasons which may not come close to the truth such as these birds could be more shy than others and prefer not to be disturbed and hence rather than foraging in the open, they move to the secluded place. And perhaps there isn't much place left for them to eat alone I guess. It would be interesting to see where else they migrate should they decide to ignore this place due to disturbance.

Above graph describes trend of some of the migratory birds found on the lake from various periods. On the x-axis, you can see the years and on the y-axis, the number represents the count of the birds during this period.

Above graph describes trend of some of the birds that reside on and around the lake from various periods. On the x-axis, you can see the years and on the y-axis, the number represents the count of the birds during this period.

Birds who live on and around the lake permanently also tell a similar trend (as shown above). So collectively all three categories - raptors, migrants and resident birds - tell the same story, that we are increasing in number. We love this place.

These may be a small list at display, however I observe similar trends in other species as well, both resident and migrant.

So why do birds migrate? Of course for better conditions for feeding, breeding and raising young ones. They mainly feed on fish, insects, other invertebrates, fruits, grains, seeds and in case of raptors they feed on small birds, small mammals, rodents etc. Hoskote lake is a large enough to contain good amount of fish for these birds to forage on, good soil quality not only to produce vegetation for these birds to perch on but also to feed on insects who come out after a downpour.

This is a current scenario on the benefits that birds, small mammals, insects and humans get from this lake. But as we know this was not the case a decade ago, two decades and beyond. Lets look at some of the maps from few decades back from 2024.

It is very much evident from these images that there is so much vegetation has been lost in the past four decades. I had drawn various points along the boundaries (approximate) of the vegetation surrounding of the lake for the map of 1985 . I then referenced same location in the maps of 2014 and 2024. It may look like the quantity of water has increased from 2014 to 2024, however I do not have any data on hydrology aspects of this region to justify. I can only assume that there were rains that might have lasted beyond the typical monsoon period in 2024. The clarity and contrast of these images was also visibly increased without any modification done from my side.

Nonetheless we see there is an increase in the concrete around the lake which could have forced many birds to not opt this place for breeding raising their young ones over these years. An increase in cement, steel and paint also means the probability of an increase in the temperature of air in this area is high. There are potential side effects such as when the air temperature increases around wetland area, the water body will absorb more heat and will evaporate more than what it normally does. Which is not good.

With the rise in the heat, people may die due to heat related cardiovascular diseases. There is one more aspect which will cause problem with this phenomena, which is the possibility of Heat Shock Proteins (HSPs) getting affected because of this increase in the temperature. I could not find any study as such which directly links affecting HSPs due to the heat generated in the Urban Heat Island, a phenomenon where an area in the urban experiences warmer than its rural parts. Now, Hoskote lake is in the rural side of Bengaluru hence the affects may not be visible as of now but if the concrete continues to occupy more space especially towards the lake then there is definitely a reason to concern. Starting with an unsettling sight of decrease in the number of birds that migrate and the ones to who stay permanently will face shortage in the food, a severe shortage of a place to take shelter, breed and raise young ones, there will be shortage of fish in the lake which are also a bread winner for the local fishermen. I am assuming there could be other side effects that may arise. Do not forget the Heat shock proteins which play a critical role in promoting tumor progression.

This lake should be protected at any cost before it experiences the weight of a bus stand, a theme park or another gated community on her heart. We have seen various disasters in the past in various parts of the country when the lakes have been replaced by construction works.