Sparrows in the news? The little brown birds that visit my yard, that I never can confidently conclude are sparrows and not perhaps wrens? Yep. These unassuming neighbors have been featured in a few science headlines over the past couple of weeks, which I thought was curious. So I thought I’d pop in this week and offer a quick summary of a few interesting stories about why scientists are taking a closer look at sparrows these days.
1. Light pollution and disease in sparrows
The first sparrow article that caught my attention adds to a growing body of information about how the environment may impact living things through their biological clocks. I intentionally keep an eye out for interesting studies on circadian rhythms because I teach an undergraduate course on this topic from time to time (see my October blog post). In their new scientific report, researchers wanted to examine connections between nighttime light exposure and West Nile virus infection in sparrows, which is spread to the birds from mosquitoes, just like it is transmitted in humans. The upshot: nighttime light may make it harder for sparrows to recover from the virus. The ramifications include sparrow individual and population health, but also potentially our own health. Many recent studies are considering how our own artificial lighting impacts both human biology and wildlife populations. It’s something to consider as we increasingly light up our world and blur the traditional distinctions between night and day for us and the other species who live in our communities.
City lights at night, as captured by astronaut Chris Hadfield on the International Space Station. Photo credit: NASA
2. Noise pollution changes a sparrow’s songs
From light pollution to noise pollution: humans impact our environment with our activities, both night and day. Canadian researchers have been studying the impact of loud industrial noise associated with oil and gas drilling on the qualities of birdsong in grassland sparrows in Canada. The online article, written by one of the original study’s researchers herself, highlights many interesting changes in acoustic patterns and discusses whether the birds are still communicating effectively with each other during mating season. Another example of “time will tell” before we know the implications for sparrows living among noisy machines, but it is nonetheless an interesting examination of how animal behaviors may undergo change (positive or negative) when sharing habitats with humans.
3. Sparrows’ bodies are shrinking
Why would sparrows be getting smaller? Who measures such a thing? Apparently wildlife biologists in Australia, who are interested in understanding the trade-offs between the warmer global temperatures associated with climate change and animal growth. My next article reports that sparrows in warmer temperatures are not as large as sparrows that lived in cooler temperatures. No one is quite sure of the long-term impact of such a change (though according the article, it has long been established that larger animal bodies store heat better than smaller ones, which can benefit animals living in colder habitats). Will warmer climates impact human growth and health as well? Scientists are studying wild populations of many different species for a wide range of possible physiological and ecological outcomes of climate change. This will help us understand the range of variables for ecosystems as well as how our own health and habitats may be impacted by warming temperatures.
4. Sparrow species in peril
The common house sparrow (Passer domesticus) is a fixture of my North American landscape. But many other species of sparrows are found around the world, and some of them are facing decline. A local news story in Miami, Florida about possible extinction of the grasshopper sparrow in Florida caught my eye as a cautionary tale about wild bird populations. These sparrows have received attention and resources for survival from their human helpers in Florida for many years as their populations have decreased, due mostly to habitat loss due to human development. But now, the birds are getting sick, and infection among young birds is making breeding less successful. This species, which was vulnerable for many reasons, may ultimately be a victim of human expansion. It highlights ongoing debates over land management, wildlife protection, and the delicate balance of the species with which we share our world. What impact does a lost species have on the ecosystem, or on our own species’ continued journey through time? Perhaps these tiny sparrows–so easily overlooked–will give us new insights. I certainly will view my own sparrow neighbors with new appreciation this year.
The endangered Florida grasshopper sparrow (Ammodramus savannarum floridanus) and a human helper. By Mary Peterson, USFWS [Public domain], via Wikimedia Commons
Bibliography:
From science journalists to the scientists themselves: people who document new science research publish their work in diverse outlets online. Links to each article are provided below. Check them out to read more, and to find additional resources for more information.
- Milius, Susan. “Light pollution can prolong the risk of sparrows passing along West Nile virus.” Science News, January 18, 2018. https://www.sciencenews.org/article/light-pollution-can-prolong-risk-sparrows-passing-along-west-nile-virus
- Staletovich, Jenny. “Time running out for tiny Florida sparrows.” January 19, 2018. Tribune News Services/Portland Press Herald https://www.pressherald.com/2018/01/19/time-running-out-for-tiny-florida-sparrows/
Cover photo: Female house sparrow (Passer domesticus) in India. Males and females have different plumage. Photo credit: House_Sparrow_(Passer_domesticus)-_Female_in_Kolkata_I_IMG_3787.jpg: J.M.Garg derivative work: Totodu74 [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)%5D, via Wikimedia Commons
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