The search for life has become one of the holy grails of science. With the increasing number of exoplanet discoveries, astronomers are hunting for a chemical that can only be present in the atmosphere of a planet with life! A new paper suggests that methyl halides, which contain one carbon and three hydrogen atoms, may just do the trick. Here on Earth they are produced by bacteria, algae, fungi and some plants but not by any abiotic processes (non biological.) There is a hitch, detecting these chemicals is beyond the reach of current telescopes.
The China Space Station Telescope, scheduled for a 2027 launch, will offer astronomers a fresh view on the cosmos. Though somewhat smaller than Hubble, it features a much wider field of view, giving a wide-field surveys that will map gravitational lensing, galaxy clusters, and cosmic voids. Scientists anticipate it will measure dark energy with 1% precision, differentiate between cold and dark matter models, and evaluate gravitational theories.
Thanks to readers who sent in photos, but we always need more!
Today’s batch comes from UC Davis ecologist Susan Harrison, and were taken near her school. Susan’s captions and IDs are indented, and you can enlarge the photos by clicking on them.
Early spring meanderings
In late February I took a visiting college friend hiking in the hills northwest of Davis, California. Starting up the trail, we had the good luck to see a tiny Northern Pygmy-Owl (Glaucidium gnoma) high in an oak. Thinking I’d captured at least a low-resolution facial photo, it turned out I’d been fooled by the false eyes on the back of the bird’s head. Pygmy-Owls prey upon and therefore are often mobbed by small songbirds. The eyespots are believed to protect the owl’s true eyes when it’s under attack.
Northern Pygmy-Owl:
We later enjoyed watching an Anna’s Hummingbird (Calypte anna) doing yoga in the sun; just like humans, they stretch to stay flexible and prepared for action:
The setting was Valley Vista Regional Park, looking south to the organic farms of the Capay Valley and east to the remarkable Sutter Buttes and Sierra Nevada.
Sutter Buttes:
Here are a few other sightings from near Davis:
Western Bluebird (Sialia mexicana):
Merlin (Falco columbarius):
White-tailed Kite (Elanus leucurus):
In early March, invigorated by recent owl experiences, I set off to the Sonoma coast in search of Northern Saw-Whet Owls (Aegolius acadicus). They are found in lushly forested canyons, and one such location near Jenner, California, sounded promising.
Waiting for nightfall, I hiked among the redwoods enjoying the startlingly loud and lovely song of tiny Pacific Wrens (Troglodytes pacificus):
Calypso Orchids (Calypso bulbosa) lit up the understory here and there:
After dark a Saw-Whet Owl began singing. After I followed it and played a few of its low toots on my phone, a small ghostly presence flapped past my head into a willow. Using a headlamp for illumination, I managed a few grainy photos.
Saw-Whet Owl:
Stopping by the coast the next morning, I saw a possible — and if so, unusual — Yellow-Billed Loon (Gavia adamsii) in front of a smaller and darker Common Loon (Gavia immer):
The mouth of the Russian River at Jenner, California:
For much of human history, wolves and other large carnivores were considered pests. Wolves were actively exterminated on the British Isles, with the last wolf killed in 1680. It is more difficulty to deliberately wipe out a species on a continent than an island, but across Europe wolf populations were also actively hunted and kept to a minimum. In the US there was also an active campaign in the 20th century to exterminate wolves. The gray wolf was nearly wiped out by the middle of the 20th century.
The reasons for this attitude are obvious – wolves are large predators, able to kill humans who cross their paths. They also hunt livestock, which is often given as the primary reason to exterminate them. There are other large predators as well: bears, mountain lions, and coyotes, for example. Wherever they push up against human civilization, these predators don’t fare well.
Killing off large predators, however, has had massive unintended consequences. It should have been obvious that removing large predators from an ecosystem would have significant downstream effects. Perhaps the most notable effects is on the deer population. In the US wolves were the primary check on deer overpopulation. They are too large generally for coyotes. Bears do hunt and kill deer, but it is not their primary food source. Mountain lions will hunt and kill deer, but their range is limited.
Without wolves, the deer population exploded. The primary check now is essentially starvation. This means that there is a large and starving population of deer, which makes them willing to eat whatever they can find. They then wipe out much of the undergrowth in forests, eliminating an important habitat for small forest critters. Deer hunting can have an impact, but apparently not enough. Car collisions with deer also cost about $8 billion in the US annually, causing about 200 deaths and 26 thousand injuries. So there is a human toll as well. This cost dwarfs the cost of lost livestock, estimated to be about 17 million Euros across Europe.
All of this has lead to a reversal in Europe and the US on our thinking and policy toward wolves. They have gone from active extermination to protected. In Europe wolf populations are on the rise, with an overall 58% increase over the last decade. Wolves were reintroduced in Yellowstone park, leading to vast ecological improvement, including increases in the aspen and beaver populations. This has been described as a ripple effect throughout the ecosystem.
In the East we have seen a rise of the eastern coyote – which is a larger cousin of the coyote, through breeding with wolves and dogs. I have seen them in my hard – at first glance you might think it’s a wolf, it does really look like a hybrid between a wolf and a coyote. These larger coyotes will kill deer, although they also hunt a lot of smaller game and will scavenge. However, the evidence so far indicates that they are not much of a check on deer populations. Perhaps that will change in the future, if the eastern coyote evolves to take advantage of this food source.
There is also evidence that mountain lions are spreading their range to the East. They already a seen in the Midwest. It would likely take decades for the mountain lions to spread naturally to reach places like New England and establish a breeding population there. This is why there is actually discussion of introducing mountain lions into select eastern ecosystems, such as in Vermont. This would be expressly for the purpose of controlling deer populations.
All of this means, I think, that we have to get used to the idea of living close to large predators. Wolves are the common “monsters” of fairytales, as we inherited a culture that has demonized these predators, often deliberately as part of a campaign of extermination. We now need to cultivate a different attitude. These predators are essential for a healthy ecosystem. We need to respect them and learn how to share the land with them. What does that mean.
A couple years ago I had a black bear showing up on my property, so I called animal control, mainly to see (and report on) what their response was. They told me that first, they will do nothing about it. They do not relocate bears. Their intervention was to report it in their database, and to give me advice. That advice was to stay out of the bear’s way. If you are concerned about your pet, keep them indoors. Put a fence around your apple tree. Keep bird seed inside. Do not put garbage out too early, and only in tight bins. That bear owns your yard now, you better stay out of their way.
This, I think, is a microcosm of what’s coming. We all have to learn to live with large predators. We have to learn their habits, learn how to stay out of their way, not inadvertently attract them to our homes. Learn what to do when you see a black bear. Learn how not to become prey. Have good hygiene when it comes to potential food sources around your home. We need to protect livestock without just exterminating the predators.
And yes – some people will be eaten. I say that not ironically, it’s a simple fact. But the numbers will be tiny, and can be kept to a minimum by smart behavior. They will also be a tiny fraction of the lives lost due to car collisions with deer. Fewer people will be killed by mountain lions, for example, than lives saved through reduced deer collisions. I know this sounds like a version of the trolley problem, but sometimes we have to play the numbers game.
Finding a way to live with large predators saves money, saves lives, and preserves ecosystems. I think a lot of it comes down to learning to respect large predators rather than just fearing them. We respect what they are capable of. We stay out of their way. We do not attract them. We take responsibility for learning good behavior. We do not just kill them out of fear. They are not pests or fairytale monsters. They are a critical part of our natural world.
The post Living with Predators first appeared on NeuroLogica Blog.