A squirrel gets a free snackCan you credit it, a hovering pigeon! Not only do I have to protect my feeders from marauding squirrels, I've a new challenge.

It's difficult to believe but this fit young, dark grey feral pigeon actually manages to hover at the feeder for at least 15 seconds, poking his head through the guardian cage and eating the seed meant for my friendly tribes of great tits, blue tits and chaffinches. it's extraordinary behaviour. Is it a form of natural selection and will it result in a new breed of hovering pigeons that will terrify the good folk of olde London town? Nah, course it won't.

It set my mind to wandering and with Tuesday 12 Feb being Darwin's birthday, I wondered whether he'd marvel at our world or feel saddened. The industrialisation that brought such prosperity for his generation has had quite an impact on the wildlife he studied. It was an innocent time for humankind and the environment. We, in contrast, live in a very complicated world. Trying to balance the needs of business, commerce, leisure, society, exploration and science with the world of conservation has surely never been so difficult. Darwin recognised the implications of introduced species and recorded how every species is adapted to suit the habitat it lives in. So, it's taken 150 years since the unveiling of Darwin's theory of natural selection for us to accept responsibility for our actions.

I did think of sending a copy of On the Origin of Species to Hilary Benn at DEFRA following the publication of that department's Water Strategy for England last week. Yes, it makes some good points and recommendations but it could and should have gone further and faster. It seems we must wait another two decades for action on flooding, drought and water pollution if Mr Benn's strategy is followed.

The document was also a damp squib when it comes to improving drainage. London desperately needs its drainage sorted to cope with the heavy downpours we see so often these days. The drains were never meant to cope with the sheer volume of water we get as a result of tropical style storms and the run-off from all the hard surfaces that continue to replace porous ones. Trees, shrubs, grass, gravel and even rubble-strewn sites help absorb excess rainwater. As development removes these porous surfaces, heavy downpours overwhelm our sewers, allowing terrible pollution of waterways and widespread destruction and damage to the environment and homes.

Grey heronIf ever you need an indicator of water quality, take a stroll along a London river or canal and look at the birds. You'll see herons, kingfishers and cormorants aplenty. They are there because there is food there, which means the waterways are pretty healthy. Until the next drain overflows! Then the fish die and the birds starve. It's very simple: Clean water plus food equals life.

The Thames is a major trunk route for wildlife, all waterways are incredibly important for our future too. You can't exploit them without seriously denting our ecosystem. Can you imagine the outrage if anyone seriously proposed, for instance, an airport in the Thames Estuary? I'm sure once he's dipped a toe in the water, Mr Benn will throw himself into the deep-end and make a firmer commitment for the sake of all our futures.