Nature Notes: The Kingfisher

I am extraordinarily lucky to live in Bristol, and have the Bristol Avon on my doorstep. I regularly travel up the river from the city of Bristol and into Somerset. Through Keynsham and Saltford, past the city of Bath and into Wiltshire up through Bradford-on-Avon. Being a pedestrian, I rely fully on the train and my feet to get me to where I want to be, and no matter where I alight, I'll be strolling up or down the river taking in the scenes and wildlife, whether there be a fishing rod in my hand or not.

Along this river there's always a creature that studies and surveys the water keenly, waiting patiently for it’s next catch, a pristine fish. But this creature is not me, or any other angler, it is a Kingfisher.
I regularly boast to others that no matter where I walk on the Avon, I will always see a Kingfisher, be I at Bradford-on-Avon further up, watching them dart up and down the river defending their territory from other Kingfishers, or perched on the handrails of boats drifting in Bristol Harbour itself.
To me, the Kingfisher is the angler's ultimate companion. Where one is present, you know the water is healthily holding plenty of fish, and when you are catching very little, if he is present, he will happily show you how it's done. That is if he stops to show off his skills. More often the angler will hear its whistling 'chee' call and see a shining azure blue flash bolt past without a moment's thought to you being there.

A Kingfisher, eyeing up its next Catch

The Blue Streak

The UK is home to the Common Kingfisher (Alcedo atthis) and is our only species of Kingfisher. This makes them very easy to identify, but not easier to spot at times, despite its vibrant colours.
The Kingfisher is a small sparrow sized bird, measuring about 16cm long as an average, and having a 25cm wingspan. Adult birds weigh around 34-46 grams, with a short little tail, and a large head compared to its body with a very long sharp bill. The upper parts of its body are coloured multiple shades of blue. Green/blue, azure and cobalt. The brightest stripe of shining blue runs down its back. 
Whereas its underparts are coloured a bright orange, and orange also appears as a part of an eye band, the back of the band being white along with its bib. A Kingfisher's legs are red in colour. Male and female birds are only visually differentiated by their beak, the lower mandible having orange markings on the female bird.
Kingfishers, unsurprisingly considering their name, feed on fish and are good indicators of the health of a freshwater habitat,
The Common Kingfisher is also found throughout Europe, Asia and North Africa, though in Africa they do tend to be a winter visitor. They enjoy a mild climate.
Kingfishers fly very fast, and usually in a direct route, low over water. They are mostly solitary birds when it's not breeding season, and roost alone, territorially protecting feeding areas by driving others off. In Autumn, their solitary lifestyle changes as they start to form breeding pairs.
They have been known to live up to 15-21 years, though many don't usually make it past one breeding season.

Kingfisher perch on Branches over a River

A Fisherman’s Home

Kingfishers are found around clear, slow flowing rivers and streams, as well as lakes with well vegetated banks. They like areas where reed beds fringe the banks or areas of scrub, with branches of trees and bushes that overhang the water, perfect areas for them to perch on to hunt. Smaller bodies of water are preferred by them over large ones. Small streams, canals and ponds being better places over large rivers and lakes. They also prefer to live around water habitats where the clarity of the water is clear, as this gives optimal visibility to hunt their prey.
In Winter Kingfishers actually become a coastal bird, with many heading towards harbours, estuaries and rocky shorelines.

A Freshly Caught Minnow

Deep Dive

A Kingfisher's main prey is fish. They eat a variety of fresh water fishes from Minnows, Stickleback, Roach, Rudd, Trout, Salmon Fry, Elvers and Lamprey. 60% of their prey are indeed fish, however, they will also take tadpoles and small frogs, and dragonfly larva and diving beetles. They particularly eat shrimp during the winter months. 
Basically any aquatic species or fry up to about 12cm in length, which is just about big enough to swallow.
Each bird must hunt, catch and consume 60% of its body weight in fish each day (which is about 16 Minnows). It is therefore essential for them to be territorial about the best hunting areas they hold.
As any angler or bird watch will tell you, it is fascinating to watch them hunt.
The ideal perch a bird will look for is one about 1-2 metres above the water level, be it a branch or a river bank overhang. The Kingfisher will bob its head from its perch, looking into the water to gauge the distance of the prey from itself. Amazingly they can allow for the refraction of the light between the air and the water to pinpoint the prey precisely. Kingfishers have two fovea rather than one. This is a small pit in the back of an eye with the greatest density of light receptors that provides the clearest vision. A Kingfisher has the ability to switch between the two as it sees into the water, from monocular vision looking through the air, to binocular vision while looking down through the water.
This ability in the air makes its vision very sharp, and it is able to judge the distance and refraction of the water, however underwater it is not as sharp, but vastly increases its ability to judge the distance of a moving prey.
They also have an oil droplet inside the cone of its eyes that enhances its colour vision, which also goes to reduce the glare of the water.
When all the factors have been judged, which only takes a fraction of a second, the Kingfisher dives down, plunging into the water like a dart to catch its quarry. As the Kingfisher hits the water, a third eyelid covers and protects its eyes, but it happens so quickly and precisely that it doesn't matter that it can visually see. The distance it is looking for between the water's surface and its prey is usually no deeper than about 25cm, so it can be a waiting game to find the right fish.
Once the fish is retrieved back up to its perch, the Kingfisher beats the fish on it several times to ensure it is dead before eating it, always head first, for ease of swallowing.
After digesting the meal the Kingfisher will regurgitate a pellet of fish bones and other indigestible items, much like an owl would, doing so about 3 times a day.
Prime hunting spots are by river bends, where the water slows and small fish move to escape the flow and get cover from overhanging plants.

A Third Eyelid covers a Kingfishers Eye as it Dives

The Burrowing Bird

Kingfisher courtship is fast paced and noisy, as expected. The male will chase the female, calling continuously. When the female is sufficiently convinced the male holds potential, courting continues with ritual feeding of the female, gifting her caught fish to prove he can provide for the young.
When paired up, they become even more territorial over their nesting location, as they are very particular about where it should be. It needs to be on an area of bank that is, more or less, vertical to the water, and devoid of vegetation. It's easier to dig a nesting burrow if the soil is looser, and there are no roots from vegetation in the way. Both birds dig a nest tunnel at the top of the bank to try to ensure that if the river floods, the nest will be safe. The tunnel itself can be anywhere between 30-90 centimetres long and gently inclined from the opening to the back to ensure that any detritus, such as fish bone pellets and waste, falls down and into the water to help keep the nest clean. The nest chamber itself is not lined with nesting material.
Kingfisher eggs are glossy and white in colour and laid at the end of their burrow between March and July to coincide with the breeding seasons of the freshwater fish they feed on.
They lay anywhere between 2-10 eggs, but with the larger number usually one or two eggs fail to hatch as the parent can't cover all the eggs to incubate them properly.
Both the male and the female take it in turns to incubate the egg during the day, but during the night it is only the female who does this.
The eggs take around 19-20 days to hatch, and 24-25 days for the young to fledge.
A Kingfisher couple can have two or three broods of young in one season in this way. Both the adults have to work hard to feed their young, for an average brood of 7 young the adults will need to catch around 5000 fish to feed them.
The feathers on the young moult from their duller colours between July and November, their black bill, and black legs and feet changing to adult colouring too.
Around 4 days after fledging, the young Kingfishers start learning diving. This is a very hard time for the young birds, as only half of them survive the first week or two. The ones that can't learn the correct diving technique, become too waterlogged and drown or starve if they don't learn how to catch enough fish in time.

A Female Kingfisher brooding her Eggs

A Hard Life

The main reason a Kingfisher dies isn't through predation, but through lack of food where their usual fishing areas ice over, or simply the cold itself kills them. Floods make catching fish in rivers difficult too, where the rivers pick up speed due to the added flow, causing the water to become more cloudy and harder to spot fish, and the flow sometimes sweeping birds away when diving. During severe winters many Kingfishers die off.
Summer floods also make feeding difficult, and if the pair cannot catch enough food during them, young often starve, or the floods destroy the nests completely. 
Only 1 in 4 Kingfishers survive their first year. Very few make it past one breeding season.
As far as predators go, their main predators are rats and cats, which can easily reach the nest sites of Kingfishers. Many also die through collisions with vehicles, and windows of properties near the water. General human disturbance of banksides around nesting birds, as well as river works, drive off adult birds and kill whole nests of young frequently too.
And of course pollution in the water is another killer. Pollution mistaken as a fish can be eaten, as well as ingested via the fish they eat. Chemicals in the water can damage their feathers making them less water proof.
In the old days Kingfishers were killed regularly by humans for their feathers. Kingfisher feathers would adorn ladies dresses and hats and was the height of fashion, as was having them stuffed and displayed in glass cages. Anglers too were a big threat to the Kingfisher, as they were also killed for their feathers, with fly makers using them to make fishing flies to catch Trout and Salmon.

Another successful Catch

Securing the Species

The RSPB estimates that there are somewhere between 4800 and 8000 breeding pairs of Kingfishers in the UK, meaning they are a bird of least concern conservationally.
However, they are still a bird that needs protecting to ensure we keep those numbers.
A lot of the Kingfishers habitat gets destroyed where natural flows of rivers and streams get diverted, ‘improved’, or restructured to fit around human development. 
Where ecological concern for the Kingfisher is considered through, human maintenance of banks can help greatly however. By clearing areas of vertical banks of vegetation, the lack of roots and stones encourages Kingfishers to nest, and preservation of existing banks ensures they do not get damaged or swept away by floods.
Under the Wildlife and Countryside Act 1981, it is illegal to take, kill or injure a Kingfisher or its nest, eggs or young. It is also illegal to intentionally disturb them during breeding season.
Pollution in rivers particularly has reduced over the years, especially runoff from farms, and Kingfisher numbers have bounced back dramatically since the changes, but still needs maintaining to ensure clean, clear living conditions for fish to thrive in.
But it's not just water authorities that can help the Kingfisher, we can help them too.
To help out the Kingfishers where they are found, people can provide perches for them to dive off. As mentioned above, the optimal height above the water is between 1-2 metres and better placed in areas above slow flowing clear water. The perch needs to be solid, so that it makes diving and precision easier on the bird.
As well as making and placing perches, you can also provide homes for Kingfishers to nest in. These nest boxes or tunnels can be purchased and dug into the bank.
Placed 1 metre above the maximum water height on a vertical river bank, and if digging in multiple boxes making them 2 metres apart, they are also good places for birds like sand martins to nest in as well. Completely burying them and ensuring the tunnel slope is set at around 10-20 degrees, you can place dry soil in the nest chamber for them to lay their eggs on. A single pair of Kingfishers may even use more than one next box, with one Kingfisher brooding the eggs, while the other prepares a second box for a second brood. Placing a few perches a few metres away from the covered box will also encourage Kingfishers to use them.

A Pre-made Kingfisher Home

Having a Kingfisher make your water its home, is something to be proud of and indeed to boast about. It is comforting to know that they are now doing well on our waters thanks to changed ideas and views on water management.
On my family fishing lakes we have had a pair of Kingfishers living there for many, many years, though clearly not the same pair. In times past they certainly used the banks of the lakes to nest in, but nowadays it seems as though they nest elsewhere, perhaps on the close by river, and use the lakes for a feeding place, particularly when the water flow in the river is high and pacy after recent heavy rain.
Last year we added metal perches for them to sit on around the lakes, and within minutes of  putting them in likely places, we noted a Kingfisher using one, and they continue to use them still. With them seemingly to struggle to survive the first year, we hope this will help them out a little and keep our resident Kingfisher population plentiful.
Of course for any angler, the ultimate Kingfisher experience is when you are sat peacefully by a river bank, perhaps quiver tipping for Chub or Barbel, with your rod poking out over the water. And as you lazily await a fish to take your bait, a Kingfisher comes along and uses your rod tip as a perch to sit on creating that true magical moment, where the angler and wildlife is, without doubt, at one.