Stress test: New study finds seals are stressed-out by sharks

Researchers test the effects predators have on their prey's cortisol levels in the wild

Date:  December 6, 2017

Source:  University of Miami Rosenstiel School of Marine & Atmospheric Science

Summary:

While a little added stress may be helpful to flee a dangerous situation, or to meet an approaching deadline, it's no secret that prolonged exposure to the stress hormone cortisol is linked to health problems. So, what effects does stress have on animals in the wild that need to navigate the same waters as the ocean's top predator -- great white sharks?

Read more  

Heart monitors on wild narwhals reveal alarming responses to stress

As sea ice melts, new findings add to concerns about the effects of ocean noise and increased human activity on deep-diving Arctic whales

Date:  December 7, 2017

Source:  University of California - Santa Cruz

Summary:

Stress from human disturbances could cause behavioral responses in narwhals that are inconsistent with their physiological capacities, researchers say. They found that narwhals released after entanglement in nets and outfitted with heart monitors performed a series of deep dives, swimming hard to escape, while their heart rates dropped to unexpectedly low levels of three to four beats per minute.

Continued  

Feces from entangled North Atlantic right whales reveals 'sky-high' stress levels

November 30, 2017

In a new study published this week in Endangered Species Research, North Atlantic right whale scientists found that whales who undergo prolonged entanglements in fishing gear endure "sky-high hormone levels," indicating severe stress, which researchers discovered using a pioneering technique of examining scat from live, entangled, and dead whales over 15 years.

"For the first time, we can get hormone levels on not just dead, but living whales," said Dr. Rosalind Rolland, D.V.M., the study's lead author and a senior scientist in the Ocean Health and Marine Stress Lab at the Anderson Cabot Center for Ocean Life at the New England Aquarium who developed this technique. "These levels show stress from extreme physical trauma. It's an animal welfare issue."

For the highly endangered North Atlantic right whale population, it was a devastating summer with 16 deaths - 12 in Canada and four in the US - due to vessel strikes and entanglements for a population that now only numbers around 450. For five of the dead whales, Rolland and the Anderson Cabot Center team were able to use this critical fecal stress hormone test to investigate the timeline of death. The levels of hormone indicated if whales died quickly or over several days or more. "This is one more tool in the toolbox for determining cause of death," she said.

Read more at: 

Looking stressed can help keep the peace

First research to suggest scratching may have evolved as a communication tool to help social cohesion

Date: September 11, 2017

Source: University of Portsmouth

Summary:

Scratching may have evolved as a communication tool to help social cohesion, new research suggests for the first time.

Scratching is more than an itch -- when it is sparked by stress, it appears to reduce aggression from others and lessen the chance of conflict.

Scratching can be a sign of stress in many primates, including humans.

Research by Jamie Whitehouse from the University of Portsmouth, is the first to suggest that these stress behaviours can be responded to by others, and that they might have evolved as a communication tool to help social cohesion.

The research, published in Scientific Reports, raises the question whether human scratching and similar self-directed stress behaviours serve a similar function.

Readon 

Support from family, friends significantly reduces stress in wild chimpanzees

Date: November 10, 2016

Source: Max-Planck-Gesellschaft

In humans and other social animals stress is associated with poor health and high mortality. These negative effects can be buffered by receiving social support from relatives or friends. However, the mechanisms responsible for this effect remain largely unknown. A team led by Roman Wittig, Catherine Crockford and Tobias Deschner from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, has studied how wild chimpanzees cope with stressful and non-stressful situations when a close bond partner is present or absent. They measured the animals' urinary stress hormone levels during episodes of intergroup conflict, grooming and resting and found that the support of a friend significantly reduced the chimpanzees' stress hormone levels, especially in situations of conflict. But even during affiliative activities with the bond partner stress levels were generally lower. Daily supportive actions by friends and family maybe key to regulating stress hormone activity, and thus the negative effects of stress, a finding with potential medical implications for humans.

Continued

We need to learn a lot more about what’s stressing whales, study emphasizes

By Virginia MorellOct. 11, 2016 , 3:30 PM
 

Human-produced noise in the ocean is likely harming marine mammals in numerous unknown ways, according to a comprehensive new report from the National Academies of Sciences, Engineering, and Medicine. That’s because there are insufficient data to determine how the ill effects of noise created by ships, sonar signals, and other activities interact with other threats, including pollution, climate change, and the loss of prey due to fishing. The report, which was sponsored by several government agencies and released on 7 October, provides a new framework for researchers to begin exploring these cumulative impacts.

“There’s a growing recognition that interactions between stressors on marine mammals can’t right now be accurately assessed," said Peter Tyack, a marine mammal biologist at the University of St Andrews in the United Kingdom, in a webinar on the report. Tyack also chaired the committee that prepared the study, "Approaches to Understanding the Cumulative Effects of Stressors on Marine Mammals."

Killer whales, for instance, are known to swim away from areas where they have encountered sonar signals of about 142 decibels, a sound level lower than currently allowed by the U.S. Navy for its ships, Tyack said, referring to a 2014 study in The Journal of the Acoustical Society of America that determined the mammals’ likely response. But scientists don’t yet know how other marine mammals might respond. They also don’t know whether or how other factors, such as encountering an oil spill or colliding with a ship, would—or would not—compound the cetaceans’ response to these sounds; or how or whether such combined stressors matter to the animals’ long-term health and overall population.

Perhaps most surprising, Tyack said, scientists’ knowledge about the population size of most marine mammals “is very poor, and too weak to detect declines in time for effective action.”

To begin filling in these many gaps, the scientists are calling on researchers to assess and report the health of individual marine mammals through observation, photography, tissue samples, analysis of waxy ear plugs, and tags that record data as the animals dive. Any changes, such as spotting skinny whales, might provide “early warning indicators” about possible population declines, Tyack said. Such data might have helped scientists figure out why an isolated population of Alaskan belugas, protected from hunting since 1999, has yet to recover.

Continued 

Stressed-out hedgehog loses its spines

Vets diagnose hedgehog with alopecia

By Nicola Harley

4:06PM GMT 04 Feb 2016

A hedgehog has lost all his spines due to alopecia brought on by his traumatic childhood.

The unusual case was discovered by vets at the A120 Veterinary Surgery near Little Hadham in Hertfordshire.

They have diagnosed Derek with alocecia after his spines began to fall out and have attributed the loss to stress.

"He's a fighter and we really want to get him 100 per cent by March so we can release him back into the wild" said Lynne Garner, who runs Herts Hogline

Lynne Garner, who runs Herts Hogline, is hoping her hedgehog will regrow his spines so he can roam free again soon.

Lynne, a published author of children's books and crafting books, said: "He's a fighter and we really want to get him 100 per cent by March so we can release him back into the wild.

"He has a very strong personality. If I try to handle him he curls up and bounces around trying to hurt me with his spines but instead I just get hit with a little ball of warm, soft skin."

"He was just a tiny hoglet - two or three weeks old and weighing 3oz - when he was found wandering in a back garden in Bishop's Stortford, Herts., last September, " she said.

Continued ...

Stressed young bees could be cause of colony declines, scientists find

Bees having to forage younger because older workers have been killed off by disease could be key factor behind colony collapse disorder

Tuesday 10 February 2015 09.28 GMT

Stressed young bees that are forced to grow up too fast could largely account for disastrous declines in populations of the insects around the world, research suggests.

Bees usually begin foraging at two to three weeks old but when older workers are killed off by disease, lack of food or other factors they have to start younger.

Scientists who attached radio tracking devices to thousands of bees found that early-starters completed fewer foraging flights and were more likely to die on their first sortie.

The phenomenon may be a key factor behind colony collapse disorder (CCD), a major threat to bee colonies – and crop pollination – around the world whose origins are still not fully understood.

Lead researcher Dr Clint Perry, from the School of Biological and Chemical Sciences at Queen Mary, University of London, said: “Young bees leaving the hive early is likely to be an adaptive behaviour to a reduction in the number of older foraging bees.

Continued ...

Squirrel Moms' Stress Aids Pup Survival

By Susan M. Reiss, National Science Foundation | December 09, 2014 12:06am ET

This Research in Action article was provided to Live Science's Expert Voices: Op-Ed & Insights in partnership with the National Science Foundation.

If jam-packed highways, back-to-back meetings and too little time for "to-do" lists make you tense, consider the red squirrels of the Yukon . Regardless of how much food they have, these mammals experience a significant amount of stress when their numbers increase.

During population booms, this compact mammal, which weighs about as much as a cell phone, breeds earlier in the year and produces smaller-sized litters with pups that grow quickly. But what cues the females to hasten their offspring's growth? To answer this question,Ben Dantzer at the University of Michigan and colleagues with the Kluane Red Squirrel Project hooked up hundreds of speakers in the forest and simulated a burgeoning population by blaring squirrel chatter.

Continued ...

Role Of Stress, Flower Loss In Bee Population Declines Investigated

Chuck Bednar for redOrbit.com – Your Universe Online

The loss of wildflowers could be a bigger threat to bee populations than climate change, but stress management could help save these essential pollinators, according to the researchers behind a pair of recently-published studies.

Experts have long known that bees, and honeybees in particular, currently face a vast array of different threats, including pesticides and the parasitic Varroa mite. Now, a paper published Monday in the journal Trends in Parasitology have found that stress could be one of the primary causes of recent widespread losses in honeybee colonies in the northern hemisphere.

More specifically, the study authors report that a complex and mysterious interplay of different stresses and their impact on the health and immune systems of bees could be at fault. As a result, bees have grown weaker and have become more susceptible to diseases that insects can ordinarily carry without issue. The Italian researchers behind the study believe that stress management and improved nutrition could help rectify the situation.

Honeybees live in complex societies frequently characterized by densely packed populations, and as a result have developed unique mechanisms for interacting with pathogens, the researchers explained. However, pathogens such as Deformed Wing Virus (DWV) can cause asymptomatic infections normally contained by their immune systems, and stress factors can synergistically promote replication of the disease and symptomatic infections.

Read more at

Stressed Out Mongooses Can't Cope with Baby Booms

By Hazel Nichols, Liverpool John Moores University | July 30, 2014 08:22pm ET

This article was originally published at The Conversation.The publication contributed the article to Live Science's Expert Voices: Op-Ed & Insights.

Many of us know from personal experience that raising children can be stressful, but a new study reveals that stress can be enough to affect the quality of parenting – in mongooses, at least.

A recent study investigates the relationship between stress hormones and parental care in the banded mongoose, a small African mammal that lives in large family groups.

Continued

Stroking Could Stress out Your Cat

Oct. 7, 2013 — A new study by an international team of animal behaviour specialists suggests that cats who reluctantly allow their owners to stroke them could be more stressed out than kitties who carefully avoid being petted.

The surprise conclusion arose in a study conducted by researchers from the University of Lincoln, UK, University of Sao Paulo, Brazil, and University of Veterinary Medicine, Austria, which aimed to better understand how cats cope with living alongside humans and other felines in a single household.

Although many people consider cats to be solitary creatures, the collaborative research, published in the Journal Physiology and Behavior and presented to an international audience in Portugal in September 2013, revealed that cats can live happily together in groups, and that the number of cats is not necessarily a problem.

Sponsored by Ceva Animal Health, the scientists examined cats living alone, in pairs and in groups of three or four in the home, assessing levels of stress hormones on four occasions.

Although the number of cats in the home did not predict background stress levels, the researchers found that younger cats (less than two years old) living on their own were more stressed than younger ones living in the larger groups.

Evidence was also found to suggest that the owner's urge to pet their cat may be a stressful experience.

Professor Daniel Mills, Professor of Veterinary Behavioural Medicine at the University of Lincoln, said: "We chose stable households to look into this question and were quite surprised by the results. Despite typically living on their own in the wild, we have known for some time that cats come together when resources like food are concentrated in a single area, for example when people feed strays. However, it might be that they do this out of need and it is still stressful for them, because they are not a naturally social species.

Continued

Stress a Key Factor in Causing Bee Colonies to Fail

Oct. 7, 2013 — Scientists from Royal Holloway University have found that when bees are exposed to low levels of neonicotinoid pesticides -- which do not directly kill bees -- their behaviour changes and they stop working properly for their colonies.

The results showed that exposure to pesticides at levels bees encounter in the field, has subtle impacts on individual bees, and can eventually make colonies fail.

This discovery provides an important breakthrough in identifying the reasons for the recent global decline of bees, a trend that has baffled many experts worldwide.

"One in three mouthfuls of our food depend on bee pollination," said lead author, Dr John Bryden from the School of Biological Sciences at Royal Holloway. "By understanding the complex way in which colonies fail and die, we've made a crucial step in being able to link bee declines to pesticides and other factors, such as habitat loss and disease which can all contribute to colony failure."

"Exposing bees to pesticides is a bit like adding more and more weight on someone's shoulders. A person can keep walking normally under a bit of weight, but when it gets too much -- they collapse. Similarly, bee colonies can keep growing when bees aren't too stressed, but if stress levels get too high the colony will eventually fail," added Dr Bryden.

"Our research provides important insights to the biology of pollinators," said co-author Professor Vincent Jansen. "It is intriguing that the way in which bees work together is the key to their success, but could also contribute to their decline and colony failure."

The research was funded as part of the £10 million 'Insect Pollinators Initiative,' set-up to understand the causes of pollinator declines and safeguard future pollination services.

"Pesticides can have a detrimental effect on bees at levels used in the field," said co-author Dr Nigel Raine. "Our research will provide important evidence for policymakers. The way we test pesticides, the way we assess their impact on bees, and the way we manage pesticides can all be improved."

http://www.sciencedaily.com/releases/2013/10/131007094510.htm

Howler monkeys increasingly stressed by human disturbance

New research shows that disturbed habitats are resulting in increasingly poor diets for monkeys, and that the additional time and energy required to find food is causing concerning levels of stress in already critically endangered primates.
January 2013. Endangered Mexican howler monkeys are consuming more leaves and less fruit as a result of habitat disturbance by humans which is forcing them to invest much more time foraging for sustenance and leading to increased ‘stress' levels, as detected through hormone analysis.

The research took place in the tropical rainforests of the Mexican state of Veracruz, which are being deforested and fragmented by human activity - primarily the clearing of forest for cattle raising. It shows that increases in howler monkey ‘travel time' - the amount of time needed to find requisite nourishment - are leading to increases in levels of stress hormones called glucocorticoids. These hormones are not only indicators of stress, but are also known to relate to diminished reproductive success and lower survival rates.

Researchers believe the study could serve as a model for behavioural change and resulting health implications more generally in primates living in habitats disturbed by human activities, such as deforestation.

Dr Jacob Dunn from Cambridge's Department of Biological Anthropology, who carried out the research, said "Howlers are arboreal primates, that is to say they spend their wholes lives in the trees. As forests are fragmented, the howlers become cut off, isolated on forest ‘islands' that increasingly lack the fruit which provide an important component of their natural diet. This has led to the monkeys expending ever more time and effort foraging for food, often increasing leaf consumption when their search is, quite literally, fruitless."

Read on: http://www.wildlifeextra.com/go/news/howler-monkeys.html

Life history and the ecology of stress: how do glucocorticoid hormones influence life-history variation in animals? – via Herp Digest

Erica J. Crespi1,*,

Tony D. Williams2,

Tim S. Jessop3,

Brendan Delehanty4

Article first published online: 11/21/12, Functional Ecology

Author Information

1School of Biological Sciences, Washington State University, Pullman, Washington, USA

2Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada

3Department of Zoology, University of Melbourne, Melbourne, Victoria, Australia

4Department of Biological Sciences, Centre for the Neurobiology of Stress, University of Toronto Scarborough, Toronto, Ontario, Canada

*Correspondence author. E-mail: erica.crespi@wsu.edu

Summary

Glucocorticoids hormones (GCs) are intuitively important for mediation of age-dependent vertebrate life-history transitions through their effects on ontogeny alongside underpinning variation in life-history traits and trade-offs in vertebrates. These concepts largely derive from the ability of GCs to alter energy allocation, physiology and behaviour that influences key life-history traits involving age-specific life-history transitions, reproduction and survival.

Studies across vertebrates have shown that the neuroendocrine stress axis plays a role in the developmental processes that lead up to age-specific early life-history transitions. While environmental sensitivity of the stress axis allows for it to modulate the timing of these transitions within species, little is known as to how variation in stress axis function has been adapted to produce interspecific variation in the timing of life-history transitions.

Our assessment of the literature confirms that of previous reviews that there is only equivocal evidence for correlative or direct functional relationships between GCs and variation in reproduction and survival. We conclude that the relationships between GCs and life-history traits are complex and general patterns cannot be easily discerned with current research approaches and experimental designs.

We identify several future research directions including: (i) integration of proximate and ultimate measures, including longitudinal studies that measure effects of GCs on more than one life-history trait or in multiple environmental contexts, to test explicit hypotheses about how GCs and life-history variation are related and (ii) the measurement of additional factors that modulate the effects of GCs on life-history traits (e.g. GC receptors and binding protein levels) to better infer neurendocrine stress axis actions.

Conceptual models of HPA/I axis actions, such as allostatic load and reactive scope, to some extent explicitly predict the role of GCs in a life-history context, but are descriptive in nature. We propose that GC effects on life-history transitions, survival probabilities and fecundity can be modelled in existing quantitative demographic frameworks to improve our understanding of how GC variation influences life-history evolution and GC-mediated effects on population dynamics

Japan Earthquake Caused Long-Lasting Stress in Dogs

Family dogs caught up in the Japan earthquake of 2011 and subsequent nuclear disaster at Fukushima showed signs of stress not inconsistent with PTSD long after the events, a new study finds.

The research compared abandoned dogs rescued from Fukushima with non-disaster affected dogs abandoned in 2009 and 2010, before the earthquake. The dogs that lived through the disaster had stress hormone levels five to 10 times higher than the dogs that were simply abandoned or found as strays.

"Long-term care and concern regarding the psychological impact of disasters appears necessary in humans and companion animals," the researchers wrote today (Oct. 11) in the journal Scientific Reports.

Continued:  http://www.livescience.com/23896-japan-earthquake-dog-stress.html

18 Beluga whales in captivity for shipment to Georgia Aquarium

Help WDCS stop 18 whales being condemned to imprisonment and an early death
September 2012. The US Georgia Aquarium is seeking to import 18 wild-caught belugas from the Sea of Okhotsk in Russia. Belugas in this area were subject to intensive hunting until the early 1960s and the population is still recovering. 

The Aquarium's excuse for the import request is that the captive beluga collection makes an important contribution to marine conservation and public education and is necessary to maintain the captive breeding population in the US.

Whale and Dolphin Conservation Society (WDCS) rejects these excuses
The commercial display industry plan to use Russian transport planes to carry the whales to Belgium - where the whales will undergo multiple transfers between shipment containers and airplanes before flying to the US and becoming the property of the Georgia Aquarium. This will subject the whales to considerable stress. Man-made noise like jet engines is a known stressor for whales, which have very sensitive hearing. It is simply not acceptable to put the whales through this - it is inhumane and violates the US Marine Mammal Protection Act.

They will be subjected to attempts at ‘breeding.' Yet, despite five decades of effort, the captive beluga breeding programme has been unsuccessful. As a result, the commercial captive industry seeks new whales to replenish its ‘stocks'.

Continued:  http://www.wildlifeextra.com/go/news/georgia-aquarium-belugas.html#cr

The End of an Era? Branding Horses Does Not Enable Them to Be Identified

ScienceDaily (Aug. 24, 2012) — Despite increasing evidence that branding foals causes the animals stress, many horse breeders still claim that this practice represents the best method for identifying the animals. Although the debate has raged for some time, nobody has thought to pose the crucial question: how reliably can brand marks be read later? This issue has now been addressed by the team of Jörg and Christine Aurich at the University of Veterinary Medicine, Vienna. The results have just been made available online in The Veterinary Journal and may well spell the end of the line for the traditional practice of branding horses.

There are many reasons why it is important to be able to identify farm animals, horses and small companion animals. Unique identification marks are essential for ensuring the correctness of breeding programmes, for preventing the spread of disease and for eliminating the possibility of deceit in competitions or when animals are sold. The traditional method of marking larger farm animals relies on branding with hot irons or on ear-tagging but this is deemed inappropriate for use on dogs and cats, which are identified by the implant of a microchip transponder. Until recently, horses were generally branded but following concerns that the practice is unnecessarily cruel there has been a gradual switch towards the use of microchips. Branding has essentially been discontinued in the European Union, although several countries still accept it and breed registries claim that this traditional method is perfectly satisfactory and obviates the need for costly equipment.

Continued:  http://www.sciencedaily.com/releases/2012/08/120824082425.htm

Drug Boosts Body's Natural Cannabis, Eases Fear in Mice

A drug that bolsters the body's cannabis-like chemicals can ease anxiety in mice, according to a new study that suggests the same brain chemistry influences how people cope with stress.

The body releases chemicals called endocannabinoids, so named because they act on the brain in almost the same way as cannabis, or marijuana, does. Much like marijuana, endocannabinoids promote relaxation. The new research finds that by halting the enzyme that breaks down an endocannabinoid called andamide, scientists can quickly train mice to get over traumatic experiences.

More importantly, people whose genes ultimately produce less of the andamide-eating enzyme have an easier time remaining cool under pressure, the researchers report today (June 12) in the journal Molecular Psychiatry.

Continued:  http://www.livescience.com/20888-drug-boosts-cannabis-eases-fear.html

Today's Environment Influences Behavior Generations Later: Chemical Exposure Raises Descendants' Sensitivity to Stress

ScienceDaily (May 21, 2012) — Researchers at The University of Texas at Austin and Washington State University have seen an increased reaction to stress in animals whose ancestors were exposed to an environmental compound generations earlier.

The findings, published in the latest Proceedings of the National Academy of Sciences, put a new twist on the notions of nature and nurture, with broad implications for how certain behavioral tendencies might be inherited.

The researchers -- David Crews at Texas , Michael Skinner at Washington State and colleagues -- exposed gestating female rats to vinclozolin, a popular fruit and vegetable fungicide known to disrupt hormones and have effects across generations of animals. The researchers then put the rats' third generation of offspring through a variety of behavioral tests and found they were more anxious, more sensitive to stress, and had greater activity in stress-related regions of the brain than descendants of unexposed rats.

"We are now in the third human generation since the start of the chemical revolution, since humans have been exposed to these kinds of toxins," says Crews. "This is the animal model of that."

"The ancestral exposure of your great grandmother alters your brain development to then respond to stress differently," says Skinner. "We did not know a stress response could be programmed by your ancestors' environmental exposures."

Continued: http://www.sciencedaily.com/releases/2012/05/120521163853.htm