Jerri-Lynn here. It’s spring migration season, with birds returning from winter sojourns in warmer climes to their summer breeding sites. The post includes some suggestions on how you can help the birds.
By Louise Gentle, Principal Lecturer in Wildlife Conservation, Nottingham Trent University Originally published at The Conversation
Now that spring is in the air, the UK is starting to see its summer visitors arriving. Ospreys are already back in their nests, chiffchaffs are singing their song to re-establish their territories, and puffins have arrived at their breeding sitesaround the British Isles.
We now know that animals migrate to increase their survival – and that of their offspring. It also helps in their quest to find food, a mate or to avoid predators.
Although we tend to think of migration as birds flying from one country to another, there are actually many animals who migrate. Wildebeest, for example, undertake a circular migration, roaming the African plains in huge numbers during the dry season in search of fresh grass. And humpback whalesmigrate to warmer waters to raise their offspring.
However, it is birds who are the record breakers when it comes to travel.
The bar-tailed godwit has the longest recorded non-stop migration, with one individual spending almost ten days travelling from Alaska to New Zealand without a break – that’s a huge journey of around 12,200km (7,580 miles).
But the Arctic tern is the true champion, making a round trip of 35,000km (22,000 miles) from the Arctic to the Antarctic and back again each year. This huge migration means that it lives in a constant summer – experiencing more daylight than any other animal – as it stops off in countries including Mauritania, Ghana and South Africa, during its global trek.
How Birds Find Their Way
Migration is a costly business – birds need to carry enough fat reserves to power their flight and sustain themselves over the duration of their journey. Getting lost could have disastrous consequences, so birds have developed incredible navigation skills to help them fly the shortest and safest routes.
Some species have an innate, inherited ability to migrate, which allows them to move to areas independently to enhance their survival.
The cuckoo, for example, is not raised by its parents as cuckoo mothers lay their eggs in nests belonging to birds of a completely different species. Yet, a young cuckoo is able to travel alone, from Europe to Africa, and back again, by using an inherited “internal GPS”.
But some species, like the Caspian tern – which undertakes a long-distance migration from its breeding home in northern Europe to its wintering location in Africa – have very little inherited basis to their migratory habits. In most cases, they are taught by their parents, also known as “cultural inheritance” or social learning.
A recent study, for example, found that young Caspians seem to learn their migratory route from their father, who carries the main responsibility for migrating with their young birds. Along the journey, he also shows them suitable stopover sites for refuelling with fish and crustaceans.
But, whether inherited genetically or socially, birds use a variety of natural cues, such as the shape of coastlines or the position of the Sun or stars –- or olfactory cues like the smell of their nest – to help them navigate their way around the globe.
Some birds, such as homing pigeons, even use a magnetic map toalign themselves with the Earth’s magnetic field as they travel.
UK’s Summer Visitors
Our knowledge of bird migration has increased dramatically since the development of biologgers, tiny data-logging devices that are attached to the birds. These allow us to track an individual’s location, speed, stopover sites and the timing of their migration.
One such study is the cuckoo tracking project. This has revealed that several cuckoos left central Africa around the start of 2022, each travelling separately for hundreds of kilometres before stopping for a couple of weeks in countries including the Ivory Coast and Morocco. They then continued with the next leg of their journey, and the most northerly bird had reached France around the 10 April. These migrating cuckoos are expected back to their breeding grounds in the UK very soon.
And they are not alone. Many birds undertake long distance migrations to the UK for the summer breeding season. For example, the wheatear also winters in Central Africa, but is back in the UK much earlier, from late February to mid August, whereas the hobby – a predator of dragonflies – winters in South Africa and is in the UK from late April to October.
This enables them to take advantage of the longer hours of daylight and abundance of food, such as insects, during the UK’s summer months.
If you’d like to help birds over their breeding season – and at the same time help other, more permanent avian residents, such as tits and sparrows – here are a few ideas.
Feeding birds nuts, seeds and household scraps such as pastry, fruit or cheese, will help to provide some easily accessible food.
But some species, such as house martins and swallows, rely on insects. So, enhancing the biodiversity in your garden by creating a wildflower meadow, or taking part in no mow May – an initiative from British conservation charity, Plantlife, asking everyone to “lock up their lawnmowers” and let vegetation grow during the month of May – will also be hugely beneficial.
Don’t forget that birds also need water, for drinking and bathing in, so a small bird bath or wildlife pond is ideal. You can also put up nestboxes to provide even more resources for our returning birds – an excellent substitute for the lack of natural nest sites for raising young, especially in urban areas.
Waking up to birdsong, courtesy of our summer visitors, including willow warblers and nightingales, brings joy to so many of us. Let’s not forget the epic journey they’ve taken to reach our shores – and do what we can to ensure a successful breeding season.
Not sure what to make of it but the past coupla days there has been a lot of stories along the lines of don’t feed the birds this spring and take down your bird feeders because of the spread of avian flu. The thing is, it seems to be like an actual campaign and if you Google the following search term, you will see what I mean-
us bird flu don’t feed birds
And these days, you can’t tell if this was put up by people actually worried by bird populations or the U.S. Poultry & Egg Association worried that these birds will spread the flu further and want people not to feed them to cull their numbers.
this strain of the flu has had an inordinate impact on wild birds, with owls and raptors especially hard hit, so that strikes me as good advice; we don’t need any more avian superspreader events…
that said, poultry losses are already nearing 30 million birds, so it wouldn’t surprise me that poultry & egg interests are pushing it
checking that, i find:
Raptor Center warns against feeding birds amid avian flu outbreak | kare11.com
Amid outbreaks of Highly Pathogenic Avian Influenza (HPAI), the University of Minnesota’s Raptor Center is urging individuals to help mitigate its spread by taking down their bird feeders and other apparatus that birds use to congregate.
Raptor Center Executive Director Dr. Victoria Hall posted of the "unprecedented" nature of the U.S. HPAI outbreak on the center’s Facebook page, and reminded the public that "all bird species are potentially susceptible to HPAI," though there is a gap of understanding in how the virus manifests in certain species over others.
"Every day at The Raptor Center, we are seeing the impact of HPAI, as we triage and test birds like bald eagles and great horned owls that are intensely suffering from fatal neurological illness due to HPAI," Dr. Hall says. "With these infected birds, humane euthanasia is the only tool we have left to help them. We also know that this strain and outbreak is causing severe illness in other species like geese, ducks, blue jays, and crows."
"During these unprecedented times, we recommend doing anything that we can to try and help our wild bird populations," Dr. Hall says. "Because the science is unclear on the role of songbirds in this current H5N1 outbreak, one consideration is to not encourage birds to gather together at places such as bird feeders or bird baths. These are places where things like viruses could easily be exchanged between individuals."
Not sure on the avian flu, but bird feeders can be vectors for many pathogens. They need to be cleaned and disinfected regularly.
Hummingbird feeder maintenance gets a lot of attention but you don’t hear much about seed and suet feeders.
There was an outbreak that impacted purple finches on the east coast years backed linked to bird feeders.
I’ve stopped keeping a bird feeder, as much as I love seeing the birds, the seeds attract too many rodents. Mice in particular. Any tips on rodent free bird feeding?
For our part we have a decent garden of wildflowers and aronia berries that I leave standing until late spring and see many sparrows and finches eating the seeds and Cardinals eating the berries from year-round.
They say the drought has caused many cranes to migrate to different places. Many stay in Nebraska. There were two flying over the grocery store parking lot on a southwest trajectory last week. They behaved as if they were looking for a good place to land and talking to each other almost constantly with a sound I cannot describe. More resonant than a chatter. Beautiful pair.
Sand Hill Cranes, maybe? In which case, agreed, a very interesting call. They don’t come through my neck of the woods, but an arresting vocalization whenever i’ve been in their range.
I saw my first Cuckoo of the year today! (heard my first two days ago but couldn’t spot it then). Southern England.
Also: first egg in my Blue Tit nest box (with camera)