Photo: by Ky Harkey of a copperhead feasting on a green anole lizard.
About this time of the year our copperheads (Agkistrodon contortrix) switch from cruising around in the evening and early night for emerging cicadas and June bugs to climbing into shrubs to feed on green anoles (Anolis carolinensis). The photo above was taken by our son-in-law Ky Harkey.
Before I go further, let me digress and discuss my position on global warming (I’ll link this to the subject of this blog later). And, yes I said “global warming,” not “climate change.” There is no doubt we are getting hotter. Almost every month and every year is setting a record for the highest average global temperature. There is almost no doubt among scientists that the cause is human activities that increase atmospheric greenhouse gases, primarily carbon dioxide and methane. And, unfortunately, the past estimates of the pace of heating have proven wrong and not in the right direction. The planet is heating up faster than expected. Many scientists fear we are nearing a positive feedback loop where heating melts tundra releasing more carbon dioxide and methane, causing increased heating, causing more melting, etc. Global warming and its associated dislocations of people, plants, and animals as deserts expand and sea levels rise will be the most significant issue of this century. It will be the crisis my grandchildren, if not my children, will have to deal with.
While there is ample scientific evidence for global warming, I have lots of anecdotal evidence too. We now have at the farm numerous birds and insects, which, as a child, I would have had to travel 250 south to Mexico to see. We can now grow tropical houseplants such as pothos ivy (Epipremnum aureum) and philodendron (Philodendron bipinnatifidum) in our yard without winter protection. Semitropical shrubs such as huisache (Acacia farnesiana) are now found north of Austin whereas when I was a child they barely survived north of our farm, which is 120 miles southeast of Austin.
A couple of weekends ago I experienced yet another example of this in a species I would have had to go to Brownsville, Texas (Texas southernmost city) to see as a child. My wife, son, and I were near Tivoli, Texas on the Guadalupe River (see my blog about this at: http://goliadfarms.com/manning-a-checkpoint-for-the-texas-water-safari-the-worlds-toughest-canoe-race/). While there we saw a pair of birds I’d never seen before. It turned out to be a pair of Great Kiskadee (Pitangus sulphurates). After getting home midweek last week I looked them up in a couple of bird guides (yes, I still use paper books sometimes). One dated 1977 and another 1987 both showed the northernmost extent of this species range to be south of Corpus Christi, Texas, over a 100 miles south of where the pair of birds was happily and noisily nesting. I was excited that I could document a range extension. Unfortunately I hadn’t taken photos so I emailed a friend and master naturalist, Wilfred Korth, to see if he’d go photograph them for me. But, he wasn’t nearly as excited. It turns out the birds have been even further north for years now. Wilfred and his wife, Claire Barnhart, live on and manage a western Goliad County (our farm is in northeastern Goliad County) ranch. He advised me Great Kiskadee had been nesting there for quite some time. So, yet another example a bird that has rapidly expanded it range northward as conditions become more like the south (one climatologist once told me that one only had to look at the climate 250 miles to see what it will be where you are before the end of the century).
Now, birds and flying insects have greater mobility than say most plants and non-flying animals. It’s not so hard for them to move 20-30 miles northward annually as things warm up. Other organisms may not be as lucky. And what about those with a barrier to movement such as island species? Many of these will go extinct.
How does this tie in with the topic of a copperhead eating a lizard? Well, the photo was taken December 26, 2015 at 9:40 AM! When I was child that never could have happened! Decembers were reliably cold enough that no snakes or lizards were active. Not only were this snake and lizard active, at least one of them was hungry and eating and in the morning well before the heat of the day.
Think carefully about this when selecting politicians to vote for. Does your choice believe in science or is he/she an anti-science denier of facts? For your children and grandchildren sake I hope you take this into consideration in the next and all elections.