Post by Eaglehawk on Sept 3, 2019 8:02:30 GMT
Barnacle Goose - Branta leucopsis
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Genus: Branta
Species: Branta leucopsis (Bechstein, 1803)
The barnacle goose (Branta leucopsis) belongs to the genus Branta of black geese, which contains species with largely black plumage, distinguishing them from the grey Anser species. Despite its superficial similarity to the brant goose, genetic analysis has shown it is an eastern derivative of the cackling goose lineage.
Taxonomy and naming
The barnacle goose was first classified taxonomically by Johann Matthäus Bechstein in 1803. Branta is a Latinised form of Old Norse Brandgás, "burnt (black) goose" and the specific epithet is from the Ancient Greek leukos "white", and opsis "faced".
The barnacle goose and the similar brant goose were previously considered one species, formerly believed to be essentially the same creature as the goose barnacle. This gave rise to the English name of the barnacle goose and the scientific name of the brant. It is sometimes claimed that the word comes from a Celtic word for "limpet", but the sense-history seems to go in the opposite direction. The barnacle myth can be dated back to at least the 12th century. Gerald of Wales claimed to have seen these birds hanging down from pieces of timber, William Turner accepted the theory, and John Gerard claimed to have seen the birds emerging from their shells. The legend persisted until the end of the 18th century. In County Kerry, until relatively recently, Catholics could eat this bird on a Friday because it counted as fish.
Description
The barnacle goose is a medium-sized goose, 55–70 cm (22–28 in) long, with a wingspan of 130–145 cm (51–57 in) and a body mass of 1.21–2.23 kg (2.7–4.9 lb). It has a white face and black head, neck, and upper breast. Its belly is white. The wings and its back are silver-gray with black-and-white bars that look like they are shining when the light reflects on it. During flight, a V-shaped white rump patch and the silver-gray underwing linings are visible.
Distribution
Barnacle geese breed mainly on the Arctic islands of the North Atlantic. The three main populations, with separate breeding and wintering ranges, from west to east, are:
Breeding in eastern Greenland, wintering on the Hebrides of western Scotland and in western Ireland, population about 40,000
Breeding on Svalbard, wintering on the Solway Firth on the England/Scotland border, population about 24,000
Breeding on Novaya Zemlya, wintering in the Netherlands, population about 130,000
A new fourth population, derived from the Novaya Zemlya population, has become established since 1975 breeding on the islands and coasts of the Baltic Sea (Estonia, Finland, Denmark, and Sweden), and wintering in the Netherlands. Its population numbers about 8,000.
Small numbers of feral birds, derived from escapes from zoo collections, also breed in other Northern European countries. Occasionally, a wild bird will appear in the Northeastern United States or Canada, but care must be taken to separate out wild birds from escaped individuals, as barnacle geese are popular waterfowl with collectors.
Ecology, behavior, and life history
Barnacle geese frequently build their nests high on mountain cliffs, away from predators (primarily Arctic Foxes and Polar Bears), but also away from food. Like all geese, the goslings are not fed by the adults. Instead of bringing food to the newly hatched goslings, the goslings are brought to the ground. Unable to fly, the three-day-old goslings jump off the cliff and fall; their small size, feathery down, and very light weight helps to protect some of them from serious injury when they hit the rocks below, but many die from the impact. Arctic foxes are attracted by the noise made by the parent geese during this time, and capture many dead or injured goslings. The foxes also stalk the young as they are led by the parents to wetland feeding areas.
Conservation
The barnacle goose is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds applies. According to Sveriges ornitologiska förening, the geese began breeding in Sweden in 1971, and according to Skansen, it was 40 years ago, more or less, when the entire population of barnacle geese left in the autumn to return in spring, soon after they began breeding in the wild.
In a warming climate, Arctic geese are rushing north
July 19, 2018, Cell Press
Barnacle geese. After nearly non-stop migration, in an attempt to cope with a rapidly warming Arctic, the geese need time on the breeding grounds to build up body stores before they can start laying eggs. Credit: Thomas Lameris/NIOO-KNAW
As Arctic temperatures continue to rise, migratory barnacle geese have responded by speeding up their 3,000-kilometer migration in order to reach their destination more quickly with fewer stops along the way, according to new evidence reported in Current Biology on July 19. Unfortunately, the birds' earlier arrival isn't making as much of a difference as one might expect. That's because, when the geese reach their Arctic breeding grounds after an accelerated marathon flight, they must take extra time to refuel their own bodies before laying eggs.
As a result of this recovery period, barnacle goose chicks continue to hatch too late to take advantage of early spring foraging opportunities. The new study shows that fewer of them are surviving long enough to leave their mothers' sides and make the trek on their own. The findings suggest that the birds are in trouble unless they start heading north for the Arctic earlier in the year, as opposed to speeding up their travel along the way, the researchers say.
"The birds are leaping in the dark as they cannot predict, while being at the wintering grounds in temperate areas, whether it is going to be an early or late spring in the Arctic," says Bart Nolet of the Netherlands Institute of Ecology and University of Amsterdam. "The weather systems in the temperate and Arctic regions are not linked, and on top of that, temperature rise is far stronger in the Arctic than in the temperate region. Only halfway through the migration, the geese are probably able to judge from environmental cues what spring will be like up in the Arctic, and they are apparently able to speed up if spring is early."
The researchers, including first author and recent graduate of the Nolet lab Thomas Lameris, combined remote sensing, bird tracking, stable isotope techniques, and field observations along the birds' entire flyway to explore the effect of climate warming on migration and breeding times of barnacle geese. The geese travel every spring from their temperate wintering and staging grounds along the North Sea coast via stopover sites along the Baltic Sea and Barents Sea to their breeding grounds in the Russian Arctic.
This animated map of goose migration strategies shows that in warm spring such as that in 2015, barnacle geese skip stopovers halfway the migration to advance arrival on their Arctic breeding grounds. Credit: Thomas Lameris/NIOO-KNAW
The evidence shows that egg laying has advanced much less than the birds' arrival in the Arctic because the geese must take time after their arrival to refuel. In years when spring came early, the geese laid their eggs well after the snow began to melt. As a result, there was a mismatch between the time that their goslings hatched and peak food quality. In years with a larger mismatch, the researchers report, goslings experienced reduced survival in the month after hatching.
The researchers say that the geese can only fully adapt to the rapid warming of the Arctic when they find ways to depart earlier from their wintering grounds. Currently, Nolet adds, barnacle geese most likely rely heavily on cues like day length that aren't changing with the temperature rise. They might also depend on other cues, including the greening of vegetation, that aren't advancing as fast in the temperate region as they are in the Arctic.
Whether these migrants can adapt their cue sensitivity and match their migration timing to changing climatic conditions remains uncertain. But there are signs that the geese may be flexible enough to adjust by other means. In fact, Nolet said that some barnacle geese have recently given up migration, breeding instead in the temperate region.
"Geese migrate in families, and young learn the route and timing from their parents," Nolet says. "On the one hand, this leads to traditional patterns; on the other hand, it can lead to rapid adjustments when some birds experience that doing the migration differently—often induced by extreme weather events—pays off."
Through comparisons of the migratory and non-migratory geese, his team hopes to learn more about the costs and benefits of migration.
phys.org/news/2018-07-climate-arctic-geese-north.html
Journal Reference:
Current Biology, Lameris et al.: "Arctic Geese Tune Migration to a Warming Climate but Still Suffer from a Phenological Mismatch" www.cell.com/current-biology/fulltext/S0960-9822(18)30745-0 , DOI: 10.1016/j.cub.2018.05.077
Highlights
•In warmer springs, barnacle geese skip stopovers to advance arrival in the Arctic
•After advanced arrival, geese need time to refuel before they can start laying
•As geese advance lay dates insufficiently, their goslings survive less well
Summary
Climate warming challenges animals to advance their timing of reproduction [1], but many animals appear to be unable to advance at the same rate as their food species [2, 3]. As a result, mismatches can arise between the moment of largest food requirements for their offspring and peak food availability [4, 5, 6], with important fitness consequences [7]. For long-distance migrants, adjustment of phenology to climate warming may be hampered by their inability to predict the optimal timing of arrival at the breeding grounds from their wintering grounds [8]. Arrival can be advanced if birds accelerate migration by reducing time on stopover sites [9, 10], but a recent study suggests that most long-distance migrants are on too tight a schedule to do so [11]. This may be different for capital-breeding migrants, which use stopovers not only to fuel migration but also to acquire body stores needed for reproduction [12, 13, 14]. By combining multiple years of tracking and reproduction data, we show that a long-distance migratory bird (the barnacle goose, Branta leucopsis) accelerates its 3,000 km spring migration to advance arrival on its rapidly warming Arctic breeding grounds. As egg laying has advanced much less than arrival, they still encounter a phenological mismatch that reduces offspring survival. A shift toward using more local resources for reproduction suggests that geese first need to refuel body stores at the breeding grounds after accelerated migration. Although flexibility in body store use allows migrants to accelerate migration, this cannot solve the time constraint they are facing under climate warming.
www.cell.com/current-biology/fulltext/S0960-9822(18)30745-0
Wild geese take climate action
by University of St Andrews
With warmer springs barnacle geese on migration use more northerly staging areas. Records of 4200 individually marked barnacle geese collected during the past 25 years showed which birds were the first to benefit from new opportunities. Some geese were sticking to their traditional staging area throughout their life (such as the left bird, marked as 3S), others (such as the right bird, marked as JL) switched at a young age to the northerly area. Photographs are taken on Svalbard, after the geese completed their migration. Credit: Jouke Prop
Migratory animals are actively adjusting their traditions to climate change, new research has found.
An international team of researchers from the University of St Andrews, with Norwegian, Dutch and British colleagues, found that barnacle geese have shifted their migratory route within the last 25 years.
In research published today in the journal Global Change Biology, the research team concluded that individual geese have decided to change to the new route, and that other geese now learn the new habit from each other.
The study is among the first to provide hard evidence that wild animals are inventing new traditions to cope with climate change.
The migratory birds, who traditionally fueled up (staged) just South of the Arctic circle in Norway on their journey from the UK to their breeding grounds on Svalbard, now mainly stage in northern Norway far above the Arctic circle.
The conclusions are based on analysis of 45 years of observations by the Norwegian Institute for Nature Research, the University of St Andrews, the University of Groningen in the Netherlands, BirdLife Norway and the British Waterfowl and Wetlands Trust.
Dr. Thomas Oudman of the School of Biology at the University of St Andrews said: "It makes sense that the birds went even further North, because where snow used to be very common there at the time of their arrival in Norway, these days it is often freshly green there: the most nutritious stage.
Coastal flats in Norway are home to barnacle geese when preparing for the migration to Svalbard. Helgeland (left photograph) has been the traditional staging area. During the past 25 years a rapidly increasing proportion of barnacle geese switched to Vesterålen (right photograph). Credit: Paul Shimmings (left) and Ingunn M Tombre (right).
"What surprised us is that it is mainly the young geese who have shifted. The youngsters are responding to a trend they could not have experienced during their short life."
Adult geese are also increasingly shifting north, although they often return to the traditional area in their old age.
Dr. Oudman added: "These patterns point at a complex social system, which enables the geese to rapidly colonize newly available areas."
Contrary to most other migratory birds, barnacle geese flourish even while their natural habitat is rapidly changing.
Barnacle geese are able to adapt to climate change due to the availability of alternative places with sufficient food at the right time, and without the threat of disturbance from humans or other dangerous animals.
The availability of alternative habitats may also help other animals to adapt to climate change. Animal species that are not so explorative and which are less sociable may take much longer to discover such places.
The paper, "Northward range expansion in spring‐staging barnacle geese is a response to climate change and population growth, mediated by individual experience," is published in Global Change Biology.
phys.org/news/2019-09-wild-geese-climate-action.html
Journal Reference:
Ingunn M. Tombre et al. Northward range expansion in spring‐staging barnacle geese is a response to climate change and population growth, mediated by individual experience, Global Change Biology (2019). DOI: 10.1111/gcb.14793
Abstract
All long‐distance migrants must cope with changing environments, but species differ greatly in how they do so. In some species, individuals might be able to adjust by learning from individual experiences and by copying others. This could greatly speed up the process of adjustment, but evidence from the wild is scarce. Here, we investigated the processes by which a rapidly growing population of barnacle geese (Branta leucopsis) responded to strong environmental changes on spring‐staging areas in Norway. One area, Helgeland, has been the traditional site. Since the mid‐1990s, an increasing number of geese stage in another area 250 km further north, Vesterålen. We collected data on goose numbers and weather conditions from 1975 to 2017 to explore the extent to which the increase in population size and a warmer climate contributed to this change in staging area use. During the study period, the estimated onset of grass growth advanced on average by 0.54 days/year in each of the two areas. The total production of digestible biomass for barnacle geese during the staging period increased in Vesterålen but remained stable in Helgeland. The goose population has doubled in size during the past 25 years, with most of the growth being accommodated in Vesterålen. The observations suggest that this dramatic increase would not have happened without higher temperatures in Vesterålen. Records of individually marked geese indicate that from the initial years of colonization onwards, especially young geese tended to switch to Vesterålen, thereby predominating in the flocks at Vesterålen. Older birds had a lower probability of switching to Vesterålen, but over the years, the probability increased for all ages. Our findings suggest that barnacle geese integrate socially learned behaviour with adjustments to individual experiences, allowing the population to respond rapidly and accurately to global change.
onlinelibrary.wiley.com/doi/full/10.1111/gcb.14793
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Genus: Branta
Species: Branta leucopsis (Bechstein, 1803)
The barnacle goose (Branta leucopsis) belongs to the genus Branta of black geese, which contains species with largely black plumage, distinguishing them from the grey Anser species. Despite its superficial similarity to the brant goose, genetic analysis has shown it is an eastern derivative of the cackling goose lineage.
Taxonomy and naming
The barnacle goose was first classified taxonomically by Johann Matthäus Bechstein in 1803. Branta is a Latinised form of Old Norse Brandgás, "burnt (black) goose" and the specific epithet is from the Ancient Greek leukos "white", and opsis "faced".
The barnacle goose and the similar brant goose were previously considered one species, formerly believed to be essentially the same creature as the goose barnacle. This gave rise to the English name of the barnacle goose and the scientific name of the brant. It is sometimes claimed that the word comes from a Celtic word for "limpet", but the sense-history seems to go in the opposite direction. The barnacle myth can be dated back to at least the 12th century. Gerald of Wales claimed to have seen these birds hanging down from pieces of timber, William Turner accepted the theory, and John Gerard claimed to have seen the birds emerging from their shells. The legend persisted until the end of the 18th century. In County Kerry, until relatively recently, Catholics could eat this bird on a Friday because it counted as fish.
Description
The barnacle goose is a medium-sized goose, 55–70 cm (22–28 in) long, with a wingspan of 130–145 cm (51–57 in) and a body mass of 1.21–2.23 kg (2.7–4.9 lb). It has a white face and black head, neck, and upper breast. Its belly is white. The wings and its back are silver-gray with black-and-white bars that look like they are shining when the light reflects on it. During flight, a V-shaped white rump patch and the silver-gray underwing linings are visible.
Distribution
Barnacle geese breed mainly on the Arctic islands of the North Atlantic. The three main populations, with separate breeding and wintering ranges, from west to east, are:
Breeding in eastern Greenland, wintering on the Hebrides of western Scotland and in western Ireland, population about 40,000
Breeding on Svalbard, wintering on the Solway Firth on the England/Scotland border, population about 24,000
Breeding on Novaya Zemlya, wintering in the Netherlands, population about 130,000
A new fourth population, derived from the Novaya Zemlya population, has become established since 1975 breeding on the islands and coasts of the Baltic Sea (Estonia, Finland, Denmark, and Sweden), and wintering in the Netherlands. Its population numbers about 8,000.
Small numbers of feral birds, derived from escapes from zoo collections, also breed in other Northern European countries. Occasionally, a wild bird will appear in the Northeastern United States or Canada, but care must be taken to separate out wild birds from escaped individuals, as barnacle geese are popular waterfowl with collectors.
Ecology, behavior, and life history
Barnacle geese frequently build their nests high on mountain cliffs, away from predators (primarily Arctic Foxes and Polar Bears), but also away from food. Like all geese, the goslings are not fed by the adults. Instead of bringing food to the newly hatched goslings, the goslings are brought to the ground. Unable to fly, the three-day-old goslings jump off the cliff and fall; their small size, feathery down, and very light weight helps to protect some of them from serious injury when they hit the rocks below, but many die from the impact. Arctic foxes are attracted by the noise made by the parent geese during this time, and capture many dead or injured goslings. The foxes also stalk the young as they are led by the parents to wetland feeding areas.
Conservation
The barnacle goose is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds applies. According to Sveriges ornitologiska förening, the geese began breeding in Sweden in 1971, and according to Skansen, it was 40 years ago, more or less, when the entire population of barnacle geese left in the autumn to return in spring, soon after they began breeding in the wild.
In a warming climate, Arctic geese are rushing north
July 19, 2018, Cell Press
Barnacle geese. After nearly non-stop migration, in an attempt to cope with a rapidly warming Arctic, the geese need time on the breeding grounds to build up body stores before they can start laying eggs. Credit: Thomas Lameris/NIOO-KNAW
As Arctic temperatures continue to rise, migratory barnacle geese have responded by speeding up their 3,000-kilometer migration in order to reach their destination more quickly with fewer stops along the way, according to new evidence reported in Current Biology on July 19. Unfortunately, the birds' earlier arrival isn't making as much of a difference as one might expect. That's because, when the geese reach their Arctic breeding grounds after an accelerated marathon flight, they must take extra time to refuel their own bodies before laying eggs.
As a result of this recovery period, barnacle goose chicks continue to hatch too late to take advantage of early spring foraging opportunities. The new study shows that fewer of them are surviving long enough to leave their mothers' sides and make the trek on their own. The findings suggest that the birds are in trouble unless they start heading north for the Arctic earlier in the year, as opposed to speeding up their travel along the way, the researchers say.
"The birds are leaping in the dark as they cannot predict, while being at the wintering grounds in temperate areas, whether it is going to be an early or late spring in the Arctic," says Bart Nolet of the Netherlands Institute of Ecology and University of Amsterdam. "The weather systems in the temperate and Arctic regions are not linked, and on top of that, temperature rise is far stronger in the Arctic than in the temperate region. Only halfway through the migration, the geese are probably able to judge from environmental cues what spring will be like up in the Arctic, and they are apparently able to speed up if spring is early."
The researchers, including first author and recent graduate of the Nolet lab Thomas Lameris, combined remote sensing, bird tracking, stable isotope techniques, and field observations along the birds' entire flyway to explore the effect of climate warming on migration and breeding times of barnacle geese. The geese travel every spring from their temperate wintering and staging grounds along the North Sea coast via stopover sites along the Baltic Sea and Barents Sea to their breeding grounds in the Russian Arctic.
This animated map of goose migration strategies shows that in warm spring such as that in 2015, barnacle geese skip stopovers halfway the migration to advance arrival on their Arctic breeding grounds. Credit: Thomas Lameris/NIOO-KNAW
The evidence shows that egg laying has advanced much less than the birds' arrival in the Arctic because the geese must take time after their arrival to refuel. In years when spring came early, the geese laid their eggs well after the snow began to melt. As a result, there was a mismatch between the time that their goslings hatched and peak food quality. In years with a larger mismatch, the researchers report, goslings experienced reduced survival in the month after hatching.
The researchers say that the geese can only fully adapt to the rapid warming of the Arctic when they find ways to depart earlier from their wintering grounds. Currently, Nolet adds, barnacle geese most likely rely heavily on cues like day length that aren't changing with the temperature rise. They might also depend on other cues, including the greening of vegetation, that aren't advancing as fast in the temperate region as they are in the Arctic.
Whether these migrants can adapt their cue sensitivity and match their migration timing to changing climatic conditions remains uncertain. But there are signs that the geese may be flexible enough to adjust by other means. In fact, Nolet said that some barnacle geese have recently given up migration, breeding instead in the temperate region.
"Geese migrate in families, and young learn the route and timing from their parents," Nolet says. "On the one hand, this leads to traditional patterns; on the other hand, it can lead to rapid adjustments when some birds experience that doing the migration differently—often induced by extreme weather events—pays off."
Through comparisons of the migratory and non-migratory geese, his team hopes to learn more about the costs and benefits of migration.
phys.org/news/2018-07-climate-arctic-geese-north.html
Journal Reference:
Current Biology, Lameris et al.: "Arctic Geese Tune Migration to a Warming Climate but Still Suffer from a Phenological Mismatch" www.cell.com/current-biology/fulltext/S0960-9822(18)30745-0 , DOI: 10.1016/j.cub.2018.05.077
Highlights
•In warmer springs, barnacle geese skip stopovers to advance arrival in the Arctic
•After advanced arrival, geese need time to refuel before they can start laying
•As geese advance lay dates insufficiently, their goslings survive less well
Summary
Climate warming challenges animals to advance their timing of reproduction [1], but many animals appear to be unable to advance at the same rate as their food species [2, 3]. As a result, mismatches can arise between the moment of largest food requirements for their offspring and peak food availability [4, 5, 6], with important fitness consequences [7]. For long-distance migrants, adjustment of phenology to climate warming may be hampered by their inability to predict the optimal timing of arrival at the breeding grounds from their wintering grounds [8]. Arrival can be advanced if birds accelerate migration by reducing time on stopover sites [9, 10], but a recent study suggests that most long-distance migrants are on too tight a schedule to do so [11]. This may be different for capital-breeding migrants, which use stopovers not only to fuel migration but also to acquire body stores needed for reproduction [12, 13, 14]. By combining multiple years of tracking and reproduction data, we show that a long-distance migratory bird (the barnacle goose, Branta leucopsis) accelerates its 3,000 km spring migration to advance arrival on its rapidly warming Arctic breeding grounds. As egg laying has advanced much less than arrival, they still encounter a phenological mismatch that reduces offspring survival. A shift toward using more local resources for reproduction suggests that geese first need to refuel body stores at the breeding grounds after accelerated migration. Although flexibility in body store use allows migrants to accelerate migration, this cannot solve the time constraint they are facing under climate warming.
www.cell.com/current-biology/fulltext/S0960-9822(18)30745-0
Wild geese take climate action
by University of St Andrews
With warmer springs barnacle geese on migration use more northerly staging areas. Records of 4200 individually marked barnacle geese collected during the past 25 years showed which birds were the first to benefit from new opportunities. Some geese were sticking to their traditional staging area throughout their life (such as the left bird, marked as 3S), others (such as the right bird, marked as JL) switched at a young age to the northerly area. Photographs are taken on Svalbard, after the geese completed their migration. Credit: Jouke Prop
Migratory animals are actively adjusting their traditions to climate change, new research has found.
An international team of researchers from the University of St Andrews, with Norwegian, Dutch and British colleagues, found that barnacle geese have shifted their migratory route within the last 25 years.
In research published today in the journal Global Change Biology, the research team concluded that individual geese have decided to change to the new route, and that other geese now learn the new habit from each other.
The study is among the first to provide hard evidence that wild animals are inventing new traditions to cope with climate change.
The migratory birds, who traditionally fueled up (staged) just South of the Arctic circle in Norway on their journey from the UK to their breeding grounds on Svalbard, now mainly stage in northern Norway far above the Arctic circle.
The conclusions are based on analysis of 45 years of observations by the Norwegian Institute for Nature Research, the University of St Andrews, the University of Groningen in the Netherlands, BirdLife Norway and the British Waterfowl and Wetlands Trust.
Dr. Thomas Oudman of the School of Biology at the University of St Andrews said: "It makes sense that the birds went even further North, because where snow used to be very common there at the time of their arrival in Norway, these days it is often freshly green there: the most nutritious stage.
Coastal flats in Norway are home to barnacle geese when preparing for the migration to Svalbard. Helgeland (left photograph) has been the traditional staging area. During the past 25 years a rapidly increasing proportion of barnacle geese switched to Vesterålen (right photograph). Credit: Paul Shimmings (left) and Ingunn M Tombre (right).
"What surprised us is that it is mainly the young geese who have shifted. The youngsters are responding to a trend they could not have experienced during their short life."
Adult geese are also increasingly shifting north, although they often return to the traditional area in their old age.
Dr. Oudman added: "These patterns point at a complex social system, which enables the geese to rapidly colonize newly available areas."
Contrary to most other migratory birds, barnacle geese flourish even while their natural habitat is rapidly changing.
Barnacle geese are able to adapt to climate change due to the availability of alternative places with sufficient food at the right time, and without the threat of disturbance from humans or other dangerous animals.
The availability of alternative habitats may also help other animals to adapt to climate change. Animal species that are not so explorative and which are less sociable may take much longer to discover such places.
The paper, "Northward range expansion in spring‐staging barnacle geese is a response to climate change and population growth, mediated by individual experience," is published in Global Change Biology.
phys.org/news/2019-09-wild-geese-climate-action.html
Journal Reference:
Ingunn M. Tombre et al. Northward range expansion in spring‐staging barnacle geese is a response to climate change and population growth, mediated by individual experience, Global Change Biology (2019). DOI: 10.1111/gcb.14793
Abstract
All long‐distance migrants must cope with changing environments, but species differ greatly in how they do so. In some species, individuals might be able to adjust by learning from individual experiences and by copying others. This could greatly speed up the process of adjustment, but evidence from the wild is scarce. Here, we investigated the processes by which a rapidly growing population of barnacle geese (Branta leucopsis) responded to strong environmental changes on spring‐staging areas in Norway. One area, Helgeland, has been the traditional site. Since the mid‐1990s, an increasing number of geese stage in another area 250 km further north, Vesterålen. We collected data on goose numbers and weather conditions from 1975 to 2017 to explore the extent to which the increase in population size and a warmer climate contributed to this change in staging area use. During the study period, the estimated onset of grass growth advanced on average by 0.54 days/year in each of the two areas. The total production of digestible biomass for barnacle geese during the staging period increased in Vesterålen but remained stable in Helgeland. The goose population has doubled in size during the past 25 years, with most of the growth being accommodated in Vesterålen. The observations suggest that this dramatic increase would not have happened without higher temperatures in Vesterålen. Records of individually marked geese indicate that from the initial years of colonization onwards, especially young geese tended to switch to Vesterålen, thereby predominating in the flocks at Vesterålen. Older birds had a lower probability of switching to Vesterålen, but over the years, the probability increased for all ages. Our findings suggest that barnacle geese integrate socially learned behaviour with adjustments to individual experiences, allowing the population to respond rapidly and accurately to global change.
onlinelibrary.wiley.com/doi/full/10.1111/gcb.14793