Behavioral ecology: Personalities promote adaptability

Date:  April 8, 2019

Source:  Ludwig-Maximilians-Universität München

Bold great tits lay their eggs earlier when under threat, the shy ones put it off. Such personality differences help maintain the biological variation essential for the survival of populations, as Ludwig-Maximilians-Universitaet (LMU) in Munich biologists have now shown.

Bird populations can adapt to environmental change, as revealed by their flexible choice of the optimal time for rearing their chicks. Thus high temperatures induce them to begin nest building and egg-laying early in the year. In colder years, they tend to postpone the whole business until later. Natural selection favors such behavioral adaptability -- provided that the required variation is available, i.e. genetic variants are present that confer 'phenotypic plasticity' on local populations. A study of great tits (Parus major), carried out by LMU behavioral biologist Niels Dingemanse and his doctoral student Robin Abbey-Lee, has now shown that this adaptability is in part attributable to differences in character and 'personality' between individuals. Their findings appear in the online journal Nature Communications.

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For these birds, climate change spells a rise in fatal conflicts

January 10, 2019, Cell Press

Researchers have found yet another way in which climate change has been detrimental to migrating birds. As European winters have become warmer, pied flycatchers traveling from Africa over long distances to reach breeding grounds in the Netherlands are arriving to find that resident great tits have already claimed nesting sites for the season. As a result, the number of flycatchers killed in great tit nests has risen dramatically. The work appears January 10 in the journal Current Biology.

"When pied flycatchers and great tits are more synchronous in their timing, this leads to a higher level of conflict over nesting sites," says Jelmer Samplonius, who did the work at the University of Groningen, the Netherlands, and is now at the University of Edinburgh, UK.

Samplonius's team got interested in the dynamics between pied flycatchers and great tits in part because both species rely on a short burst of food resources—caterpillars—to raise their young. When the birds' timing is well matched with the caterpillar peak, they are more successful in raising their offspring.

Given the reliance on the same food and nesting resources, it was clear the two species interacted quite a bit. Pied flycatchers were known for trying to take over great tit nests. They also eavesdropped on resident great tits to gain information the long-distance migrants otherwise lack about local conditions.

After years of careful monitoring, Samplonius says, "it was hard not to notice" that many flycatchers were dying in great tit nests. In other years, "virtually none" met that same fate. Could synchrony between the two competitor species explain the variation?

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Birds choose their neighbors based on personality

Date: May 7, 2017

Source: University of Oxford

Birds of a feather nest together, according to a new study which has found that male great tits (Parus major) choose neighbours with similar personalities to their own.

Oxford University researchers investigated whether the personality of birds influences their social lives -- in particular who they choose to nest near. The study involved analysing social network structure in a population of wild great tits at Wytham Woods, Oxfordshire, over six consecutive breeding seasons.

Lead author and doctoral student Katerina Johnson explained: 'We found that males, but not females, were picky about personalities, with males opting for like-minded neighbours. Our results emphasise that social interactions may play a key role in animal decisions.'

This tendency for males to associate with other males of similar personality may be particularly important during the breeding season when aggression peaks. Males fiercely defend their territories and compete for opportunities to mate with females and so shyer males may avoid setting up home near bolder, more aggressive individuals. Females, however, likely choose where to nest based on the attractive qualities of males.

The results also showed that this personality assortment amongst males was not affected by local environmental conditions. 'Just like students choosing their flatmates," Katerina commented, 'birds may pay more attention to who they share their living space with than simply location." She added: "Animal personalities can influence their social organisation and humans are likewise known to form social networks based on shared attributes including personality.'

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Birds choose spring neighbors based on winter ‘friendships’

 Date: September 14, 2016

Source: Oxford University

Great tits pick their spring breeding sites to be near their winter flockmates, according to new research into the social networks of birds from the University of Oxford.

The study shows that as mated pairs of great tits settle down to breed in the spring, they establish their homes in locations close to their winter flockmates. They also arrange their territory boundaries so that their most-preferred winter 'friends' are their neighbours.

The findings give new insights into the social behaviour of birds and demonstrate how social interactions can shape other aspects of wild animals' lives, such as the environmental conditions they will experience based on their choice of home location.

The research is published in the journal Ecology Letters.

Lead author Dr Josh Firth, of the University of Oxford's Department of Zoology, said: 'The great tits we study are a good general model for many other bird species. They form large flocks in the winter, when they're searching for food, and then each pair chooses a single set breeding site where they will be located throughout the spring as they build a nest and raise their chicks.

'We show that they appear to choose their spring breeding sites to stay close to their winter flockmates. Not only do they nest closest to the birds they held the strongest winter social bonds with, they also appear to arrange their territories so that they share home boundaries with those birds.'

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Male tits would rather starve than give up their partner, study suggests

Oxford University found male great tits would rather starve than leave their mate

By Sarah Knapton, Science Editor

12:01AM GMT 13 Nov 2015

It is said that the way to a man’s heart is through his stomach, but a new study suggests that when it comes to love males will actually forgo food rather than give up their mate.

Oxford University has been monitoring the great tits of Whytham Woods, in Oxfordshire, to test the strength of the bond between mating pairs.

Much like humans, birds tend to be socially monogamous: they find a partner to mate with and remain exclusive with this partner for many seasons.

However researchers thought that they may split up if being together meant that one had to sacrifice eating.

To test the theory they created two special bird boxes full of seed which had electronic doors that could only be opened in the presence of special radio tags attached to the bird’s legs. The male tit could not open the female’s seed box, and vice versa.

But rather than going their separate ways in their hunt for a meal, researchers found that the male stayed with the female, even when it meant starving.

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How a pair of Great Tits can lead to cheating, betrayal and divorce

IF YOU are fed up with television soap operas, then get a bird table – they offer a peep into a world of betrayal, cheating and divorce.

By STUART WINTER

PUBLISHED: 00:01, Wed, Oct 14, 2015 | UPDATED: 10:40, Wed, Oct 14, 2015

Those cheeky great tits feasting on peanuts are far from just humble garden birds, but fascinating characters with lives as tempestuous as any character in Coronation Street or Albert Square. 

Oxford University scientists have discovered how the birds have a complex social whirl that influences whether they stay loyal to a partner or head to the avian equivalent of the divorce courts. 

After looking into the lives of 58 pairs of great tits, the researchers made a fascinating number of discoveries about the common garden birds famed for their bright blue and yellow plumages.

Birds, like humans, tend to be monogamous, preferring to remain “socially exclusive” with their breeding partner, but the scientists found male great tits can turn into the equivalent of a soap opera love rat. 

Males will separate if they feel a new female on the block offers more in life than the previous nesting season’s partner. 

For female great tits, however, the research team think they make partnership decisions on the quality of a male’s nesting territory rather than his personal attributes.

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Climate change and bird competition

Posted on: 03 May 2015

New research on Blue and Great Tits has revealed that long-term climate change could badly affect the survival rates of different bird species living in the same areas.

A team from Swansea University’s College of Science examined competition between Blue and Great Tits at four sites in Europe. The study focussed on two sites in Belgium, one in The Netherlands and one in the UK. All were home to breeding pairs of both species and had hosted annual counts of the two species for more than 15 years.

Dr Fowler said: “Blue Tits and Great Tits compete for both food and roosting sites, but they generally coexist with each other. As we know that climate fluctuations can affect the distribution, behaviour and life cycle of plants and animals, we set out to find whether climate change could change the competitive relationships between these two bird species.”

The aim of the research team was to examine whether the strength of competition between Great and Blue Tits had changed over time, and if this could be linked to climate fluctuations to enable them to better forecast the consequences of the change in the strength of competition for species co-existence.

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Neighboring birds sing 'out of tune'

Date:

February 18, 2015

Source:

PLOS

Geat tits living next to each other may sing their songs at significantly different rates, more or less frequently, as compared to non-neighboring birds, according to a study published February 18, 2015 in the open-access journal PLOS ONE by Lysanne Snijders from Wageningen University, Netherlands and colleagues.

Great tits are territorial and use their song to signal their territory to unfamiliar potential competitors and familiar neighbors, where boundaries have likely already been established. To investigate how signal traits vary in relation to the overall social environment, the authors of this study tested whether neighboring birds sharing a territory boundary, rather than birds just flying in the area, is related to similarity in dawn song traits between territorial wild great tits.

Researchers collected song recordings from over 70 unique male great tits at dawn, during the breeding season, and compared songs between neighbors and non-neighbors.

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Being lower in pecking order improves female tit birds' memory

Date:

December 9, 2014

Source:

Springer Science+Business Media

Summary:

When it comes to remembering where a tasty titbit was left, female great tit birds are miles ahead of their male counterparts. This ability might have evolved because the females come second when there’s food to be shared.

Great tits (Parus major) are highly intelligent and quick learners. These common European songbirds have interesting and ever-changing ways in which they find food, and even use tools such as conifer needles during foraging. Unlike most other members of the tit family, great tits are not food hoarders. Brodin and Urhan have previously demonstrated that they are able to observe where their hoarding relatives have made a stash, only to retrieve it up to 24 hours later.

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Birds conform to local 'traditions'

Date:

December 3, 2014

Source:

University of Oxford

Summary:

Birds learn new foraging techniques by observing others in their social network, 'copycat' behavior that can sustain foraging 'traditions' that last years, according to a study of how innovations spread and persist in wild great tits -- Parus major.

The study involved experiments with eight local populations of great tits in Wytham Woods, Oxfordshire (UK). In five of the populations two male birds were trained to slide a puzzle box door either to the left or to the right. In three control groups two males were captured but not trained. The birds were then released back into their original populations to act as 'innovators', together with puzzle boxes that revealed a tasty mealworm reward when opened from either side. Electronic tags on the birds recorded how the two box-opening methods spread in each of the local populations through social network links.

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