Red knot individual personalities, new study

This November 2016 video says about itself:

Saving the Red Knot

The Red Knot flies each fall along two crisis-ridden migratory routes. One is the East Asia-Australasia Flyway, where many stops along the way have been damaged due to reclamation and other human activities.

The other route, across the United States to a winter destination in Tierra del Fuego at the southern tip of South America, is threatened in part by overharvesting of horseshoe crabs.

Eats: Invertebrates, especially bivalves, small snails, and crustaceans. During breeding season, also eats terrestrial invertebrates.

Behavior: Male makes an aerial singing display. Pecks at surface for prey or probes for buried prey. Swallows small mollusks whole. Despite their gregariousness during the winter, pairs maintain breeding territories and generally nest about 1 km (0.7 mi) apart from each other.

Conservation: Red Knot is a global species. The IUCN Red List lists Red Knot as a Near Threatened species. The occurrence of large concentrations of Knots at traditional staging areas during migration makes them vulnerable to pollution and loss of key resources. At its peak, the Red Knot population in Hebei’s Luannan Wetland [in China] was 60,000. However, in recent years due to the reclamation of surrounding areas and other factors, by 2015 the number had dropped to just over 20,000.

There are three subspecies in North America, and they all appear to be in decline. The populations wintering in South America dropped over 50% from the mid-1980s to 2003, and are listed as a federally threatened species in the United States. A 2012 study estimated the total number of all three North American subspecies at about 139,000 breeding birds. The North American Red Knot is on the “2014 State of the Birds Watch List”, which lists bird species that are at risk of becoming threatened or endangered without conservation action. This is in line with the situation in China, which means that the birds will become threatened or endangered if protection measures are not taken.

From the University of Alberta in Canada:

Bird personalities influenced by both age and experience, study shows

New research examines development of personality in birds

June 6, 2019

For birds, differences in personality are a function of both age and experience, according to new research by University of Alberta biologists.

The study examined the red knot, a medium-sized shorebird that breeds in the Canadian Arctic and winters in North Western Europe. The researchers studied 90 birds over a two year period, comparing behavioural and physiological traits of two age cohorts: adult and juvenile birds. Studying two age groups allowed the researchers to determine which changes were due to age versus time in captivity.

“During this time, birds had the same type of life experience, including varied diet,” explained Kim Mathot, assistant professor in the Department of Biological Sciences and Canada Research Chair in Integrative Ecology. “At the start of the experiments, individuals showed differences in their behaviour. We looked at whether these differences disappeared in the course of the study, which would suggest that there is something about individually variable experiences that helps maintain differences, because in our experiments, all these birds had the same experience.”

Exploring nature and nurture

The results? Well, it’s complicated.

The causes of variation among individual birds were different for different traits. For the birds in this study, individual differences in behaviour were maintained over the course of the study. But physiological traits, such as the size of each bird’s gizzard, became more similar.

“The world isn’t simple, so it makes sense that there isn’t a straightforward answer for how and why individuals differ,” added Mathot. “Nature is wonderfully complex. This is yet another example of that at play.”

In the next leg of the research, PhD student Eva Kok will follow a smaller subset of the study’s birds after they’ve been released back into the wild in order to examine how the traits measured in the lab translate to real life.

“We’re curious to see if physiological differences will reappear after release back into the wild,” explained Mathot. “For instance, if an individual had a relatively large gizzard when we initially captured it but that became smaller in captivity, will it grow to be relatively large again when re-released? Or did we shuffle the deck, and now birds can go onto different trajectories than what they were on before?”


3 thoughts on “Red knot individual personalities, new study

  1. Pingback: Guillemots, waders of Terschelling Island | Dear Kitty. Some blog

  2. Pingback: Shorebird conservation, new research | Dear Kitty. Some blog

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.