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Danger warning! How the Richardson’s ground squirrel uses an ultrasonic alarm call.

Did you know that the Richardson’s ground squirrel uses an ultrasonic alarm call to warn its fellow colony members that danger may be approaching?

The Richardson’s ground squirrel, also referred to as a gopher, prairie gopher, yellow gopher, flickertail or picket pin, can be found all over Alberta, Saskatchewan, Manitoba and into the United States. This ground squirrel likes to keep its burrow in sight at all time, hence why they can be found in pastures and parkland, away from bushes and other more dense shrubs (City of Calgary).

Richardson’s ground squirrels live semi-communally, as a female will only tolerate the presence of other females that to whom she is closely related (Wikipedia). These ground squirrels will group their burrows closely together.

A favourite prey of many hawks, the Richardson’s ground squirrel has more than one method for warning their fellow colony members that danger may be approaching. When they sense danger, they may produce an audible alarm call, or an ultrasonic alarm call. These ultrasonic calls communicate very specific information, and studies have show that the type of call may vary, depending upon the predator. The Richardson’s ground squirrel is able to discriminate among callers based on the call, which is around the frequency of approximately 48 kilohertz, far too high for humans and, more importantly, many of their predators to hear (New Scientist).

When scientists studied the response of fellow Richardson’s ground squirrels to one of these calls, they found that the squirrels recognized the calls as a warning, and were visibly more vigilant, scanning the area for predators (New Scientist).

You can recognize the Richardson’s ground squirrel by its dark brown upper side and tan belly. They have shorter, less bushy tails than other ground squirrels, and small, short ears that can look more like holes. The next time you stumble across one, try to notice if you can spot its mouth or throat moving. If so, and you hear no sound, they might just be warning their colony mates with their ultrasonic call about a potential predator – you!

The Richardson’s ground squirrel shown in the image above is currently recovering at AIWC after suffering head trauma.

References and Further Reading

“Gophers”. www.calgary.ca, 2017: http://www.calgary.ca/CSPS/Parks/Pages/Planning-and-Operations/Pest-Management/Gophers.aspx. Accessed 26 Mar. 2018

“Richardson’s ground squirrel”. www.en.wikipedia.org, 25 Mar. 2018: https://en.wikipedia.org/wiki/Richardson%27s_ground_squirrel. Accessed 26 Mar. 2018

“Ground squirrels scream ultrasonic warning”. www.cbc.ca, 28 Jul. 2004: http://www.cbc.ca/news/technology/ground-squirrels-scream-ultrasonic-warning-1.503012. Accessed 26 Mar. 2018

“Ground squirrels ultrasonic squeaks revealed”, Muir, Hazel. www.newscientist.com, 28 Jul. 2004:  https://www.newscientist.com/article/dn6216-ground-squirrels-ultrasonic-squeals-revealed/. Accessed 26 Mar. 2018

What do birds eat and how do they eat it?

Have you ever wondered what a bird eats in the wild? Obviously bread is not found in the wild, nor should it EVER, under ANY circumstance be fed to a wild bird (see https://www.aiwc.ca/do-not-feed-the-ducks/). So what do they eat? How do their diets differ in the winter than in the summer? Also, how do they access their food? Do they have special adaptations to allow them to eat certain things? Hopefully this blog will answer some questions you might have about a bird’s diet, and how a few species have evolved with their diets!

Birds that stick around during our winter season in Canada don’t have as wide of a variety of food in winter as they do the rest of the year.

  • Songbirds that stay in the Calgary areas, such as chickadees and nuthatches, are heavily dependent on stores of food that they’ve cached (hidden) throughout the year, and seeds and nuts found on conifer trees in the winter (Cornell 2017a).
  • Magpies, crows and ravens (and other corvids) are opportunistic eaters and often scavenge throughout the winter for seeds, carrion (carcasses), and will also prey upon squirrels, voles and even other birds (Cornell 2017b). Magpies are even known to pick ticks off of cattle, moose and deer (Cornel 2017b).
  • Some ducks and geese that stay all winter rely primarily on seeds, including agricultural grains, for their main food sources (Cornell 2017c,d).

As more birds are returning north after their winter migrations, their food sources are also becoming more plentiful.

  • Songbirds can start to include more insects, wild fruit and a wider variety of seeds and nuts.
  • Corvids also include more insects and wild fruit into their diets, as well as the eggs of other birds, the young of birds and small mammals, and even amphibians.
  • Waterfowl rely more heavily on aquatic vegetation, aquatic insect larvae, earthworms, snails and freshwater shrimp (Cornell 2017d).

Patients at AIWC receive balanced diets that attempt to mimic the nutrients they would find in the wild. Various household fruits and vegetables, as well as mealworms, eggs, and a variety of seeds and nuts are some of the items you would find in AIWC’s kitchen on any given day. Vitamins and supplements are often added to patient’s meals to ensure they recover back to full health prior to release.

Interestingly, birds have physical adaptations that have evolved over time to allow them easier access to their food sources. Here are just a few of them!

  • Of the 10,000 birds species on earth, only 5 have crossed bills and they are all in the finch family (Cornell University 2017e). A crossed bill refers to when the upper and lower parts of the beak do not line up and cross over each other when they are closed. This type of bill or beak is adapted to reach seeds deep in some tree cones that other birds cannot reach. The white-winged crossbill is an example of a bird that has this adaptation and is found in the Calgary region. Similar to right a left-handed people, not all crossed bills cross in the same direction!
  • Birds such as woodpeckers have adapted to be able to peck at the bark of trees to find sap or insects hiding below (Cornell University 2017f). Not only are their beaks, necks, and skulls incredibly strong, but their tails feathers and feet are also adapted to help grip  the trunk of a tree as they stand on it and peck. Woodpeckers also have incredibly long tongues to penetrate the holes they peck to get at the insects and sap. Their tongues wrap around their skulls all the way to just behind their eyes!
  • Ducks bills have evolved to allow for efficient foraging in water. The outer edges of a duck bill are soft, and are used to feel for their food (Ducks Unlimited 2018). Ducks bills have a point at the end that is used for moving food, similar to how we would use our fingernails (Ducks Unlimited 2018). On the inside of a duck bill you will find lamellae. Lamellae look like teeth, and act like a filter to separate food from non-food items when foraging in the water.

Next time you are outside and observing the birds around you, stop and assess what type of food they are eating and how they are eating it! You might be surprised to notice what they are eating and how they’ve adapted to eat it!

As the spring season begins to ramp up, AIWC will be expecting increasing numbers of patients we receive. Food is vital in the rehabilitation of patients! If you would like to contribute to the care of our patients, please visit our donation page (https://aiwc.shop/products/donate-to-aiwc).

Please feel free to leave a comment below about a special food-related adaptation you’ve noticed!

By Tayler Lafreniere, AIWC Volunteer

References:

Cornell University. 2017a. Red-breasted Nuthatch: Life History. The Cornell Lab of Ornithology. Available at: https://www.allaboutbirds.org/guide/Red-breasted_Nuthatch/lifehistory#food. Accessed March 12, 2018.

Cornell University. 2017b. Magpie: Life History. The Cornell Lab of Ornithology. Available at: https://www.allaboutbirds.org/guide/Mallard/lifehistory#food.  Accessed March 12, 2018.

 

Cornell University. 2017c. Canada Goose: Life History. The Cornell Lab of Ornithology. Available at: https://www.allaboutbirds.org/guide/Canada_Goose/lifehistory#food. Accessed March 12, 2018.

Cornell University. 2017d. Mallard: Life History. The Cornell Lab of Ornithology. Available at: https://www.allaboutbirds.org/guide/Mallard/lifehistory#food.  Accessed March 12, 2018.

Cornell University. 2017e. White-winged Crossbill Foraging Adaptation. Available at: https://academy.allaboutbirds.org/white-winged-crossbill-foraging-adaptation/. Accessed March 12, 2018.

Cornell University. 2017f. Built to Peck: How Woodpeckers Avoid Brain Injury. Available at: https://academy.allaboutbirds.org/built-to-peck-how-woodpeckers-avoid-brain-injury/#_ga=2.244171203.770611876.1520903819-543352664.1407089867. Accessed March 12, 2018.

Ducks Unlimited. 2018. The Scoop on Duck Bills. Available at: http://www.ducks.org/conservation/waterfowl-research-science/the-scoop-on-duck-bills. Accessed March 12, 2018.

What’s in a Name? Comparing the Rabbit and the Hare

Although the terms “rabbit” and “hare” are often used interchangeably, did you know that rabbits and hares are actually different animals?

While both animals belong to the same family, Leporidae, they are actually different species. Hares are typically larger, with longer ears, and are less social than rabbits. Rabbits live in colonies, which is why many have rabbits, not hares, as pets (National Geographic). Hares are faster than rabbits, and have longer, stronger hind legs, allowing them to reach speeds of 37 body lengths per second (National Geographic). Compare this to the fastest human runners, who can run only 6 body lengths per second!

While both species will molt and grow new fur in the spring, hares grow white fur during the winter. Both species live for approximately six years (AEP).

Rabbits are known for their underground burrows, but hares live aboveground. Newborn hares are born fully developed with open eyes and fur and are able to fend for themselves almost immediately, while newborn rabbits have closed eyes and no fur, and are reliant on their parent as they continue to develop. While rabbits tend to be calmer, hares spook easily. During mating season, the female hare will make the male hare chase her over several miles, and if he catches her, she will mate with him, but may throw a punch or two at him before she lets him mate her (National Geographic).

As the warmer weather approaches and baby rabbits and hares are born, it’s important to remember that mother hares and rabbits may leave their babies on their own for the day to avoid attracting predators. So if you see a nest of baby rabbits or hares on their own, don’t panic, and call us for advice before intervening!

 

Sources and Further Reading:

“What’s the Difference Between Rabbits and Hares?” www.nationalgeographic.com, Dec. 19, 2014: https://news.nationalgeographic.com/news/2014/12/141219-rabbits-hares-animals-science-mating-courtship/

“Dare to Compare the Rabbit and the Hare” www.albertaep.wordpress.com, Mar. 24, 2016: https://albertaep.wordpress.com/2016/03/24/dare-to-compare-the-rabbit-and-hare/

All About Biodiversity

What is biodiversity?

Biodiversity can be defined as the variability of all living organisms in all ecosystems (including terrestrial, marine, etc.) and the ecological functions and complexes that they contribute to (UN 1992, WWF) (fig.1).

The term was coined from the field of conservation biology, during the “National Forum of Biodiversity” in 1985, and the subsequent book, The Diversity of Life (Wilson, E.O. 1992) to draw attention to the increased number of species becoming extinct due to human interference. However, as pointed out in What is Biodiversity? (Maclaurin, J & Sterelny, K.), biodiversity cannot accurately be measured by species count alone.

A better way of visualising it is as species richness, or what ecosystem functions and importance that each individual species provides to the ecosystem itself. Are they primary producers, do they provide habitat for other species, or do they provide natural resources?

A wide range of species that provide these essential ecosystem functions is necessary for the system to thrive, and if biodiversity (or the number of species providing these functions) is high, then the loss of one species may be dampened by the presence of similar species that provide similar functions.

Fig.1 Various ecosystem services and the sources that provide them (Source: WWF)

Why is biodiversity important to the environment?

Because every species in an ecosystem contributes in some way to its function, the greater the diversity of species, the less susceptible the ecosystem is to destabilization. There are many potential impacts on ecosystem function, ranging from natural (such as forest fires and floods) to man-made (such as deforestation and farming) and it is important to understand the effects of each on the individual species.

Examples of ecosystem functions that are important for the wider environment are the nitrogen cycle (fig.2), which is extremely important for plant life, and in turn, everything that depends on plant matter, pollination, necessary for the spread of flower and tree species, and soil formation processes that enable the growth of a larger range of species than is typically possible.

Fig.2: The nitrogen cycle is an example of an ecosystem function that depends on a wide variety of organisms (Source: Environmental Protection Agency, c/o Wikipedia).

 Why is biodiversity important to us?

We may tend to think as humans being separate from the ecosystems they inhabit and contribute to, but this is not necessarily correct. A great deal of our success and wellbeing is owed to the many organisms that make up our greater environment.

Agricultural biodiversity, for example, is important in the foundation of crop development and food security, and the resilience to pests and natural disasters (UN CBD).

Medical research is also another reason why biodiversity is important. New species that provide medical benefits to humanity are discovered regularly, as was the case of the waxy monkey frog which was found to have several important peptides that it secretes from its skin and is currently being used to treat cancer patients (Eurekalert 2011).

Loss of biodiversity effects all aspects of the ecosystem, and the removal of certain species may form a domino effect, creating further loss both for humans as a species and the environment.

What can we do to preserve biodiversity?

As always, increasing public knowledge and understanding of the importance of biodiversity is a top priority when it comes to helping preserve it. If you are aware of an ecosystem or natural habitat that is vulnerable, leaving the area and animals (especially nesting sites) undisturbed is the best way to preserve biodiversity on the individual level (Naturetrust BC). Also, it’s important to participate in environmentally-friendly practices, such as recycling or reducing vehicular transportation, and reducing the use of products and materials that negatively impact the environment such as certain pesticides.

At a wider level, participating in park volunteer work and land stewardship is a great way to get involved in protecting our biodiversity, as well as getting in touch with local government if you have concerns about particular areas, environments, or species.

By Jonathan Poll, AIWC Volunteer

Sources

http://www.globalissues.org/article/170/why-is-biodiversity-important-who-cares#WhyisBiodiversityImportant

https://www.cbd.int/doc/health/cohab-policy-brief1-en.pdf

https://en.wikipedia.org/wiki/Nitrogen_cycle

https://www.eurekalert.org/pub_releases/2011-06/qub-sup060611.php

http://www.wwf.eu/what_we_do/biodiversity/

https://www.naturetrust.bc.ca/conserving-land/what-can-we-do