Most of us are aware of the notion that a pebble dropped into the ocean will, via a cascade of interconnected mechanisms, eventually affect the entire ocean. Sounds far-fetched, but the idea holds more truth than most people wish to accept.

Such cascades of related events certainly have happened all through the millions of years since life first appeared on Earth, with most of them developing slowly, over long periods of geologic time. The rapid rate of Climate Change today is making it possible to see many examples of how small alterations in the environment or in the life of some organism can kick off a cascade of events that will ultimately be bad news for one or more species. 

Let’s begin with a local but rather restrictive example. During those years when those of us now living at Meadowlark were kids, the northern bobwhite quail was a very common bird in northeast Kansas. I recall that as late as the fall of 1986, when my father-in-law was a patient in the nursing unit here, I would push him — in his wheelchair — outside on the west side of the building. He loved to sit and listen to the bobwhites calling to each other, to see them feeding among the prairie grasses, or to admire a lone sentry quail sitting on a fence wire or low tree limb.   

My late wife, Imogene, and I noticed the absence of bobwhites soon after moving back to Kansas and to Meadowlark in May of 2010. We had lived out-of-state for 47 years. I questioned wildlife biologists, but carried the personal assumption that the wild turkey, which had been successfully reintroduced to this area during those same 47 years, was a big part of the problem. The wildlife biologists said no. The only correlation they could find was between quail population numbers and the density of vegetation in the patches of sumac and dogwood in which coveys of quail spent many hours during any given 24-hour cycle. 

Warmer average temperatures can be strongly related to increased plant growth. I’ve noticed that the vegetation (even with trees) seems more dense along creek banks as I’ve pursued the Sport of Kings with one or another of my flyrods. But density of vegetation! A bit of perspective here: We humans, who tend to be very particular about our immediate personal habitats, surely can relate to something like that.    

Here’s another seemingly innocent and benign set of circumstances that can cause real trouble for certain organisms. In this also close-to-home example, involving Bayer Pond on our Meadowlark campus, the worst case scenario could have happened but did not — in this instance. A path to winter fish kill usually centers around the algae and other green water plants in the pond, their photosynthesis, and the oxygen produced from their photosynthetic activities.

A healthy body of water will have a large algae population of numerous species, although about the only time we notice pond algae is during summer when certain species of algae grow wildly and coat the pond surface with what we refer to derisively as pond scum. If something happens to kill most or all of the algae in the pond, microbes present will always move in to decompose the dead algae. Not only is the pond’s internal oxygen supply shut off, but also, these microbes, as do we, use up oxygen during their normal bodily respiration and metabolism. Thus, the pond water oxygen levels may become low enough to trigger a fish kill. And sometimes the kill can be massive when related to the size of the pond’s fish population. 

Winter fish kills usually occur when snow covers an ice-coated pond or lake long enough to shut off the sunlight necessary for the algae and other water plants in the pond to survive and produce the necessary oxygen. This past winter, snow covered Bayer Pond for many days, but the mechanical aerator ran constantly, perhaps staving off a fish kill — or at least a significant kill. Perhaps some fish died from lack of oxygen, and I, touring the pond no more than once each week during that time, could have missed it.

A side point of interest may be that the fish we know as the carp is about the last to succumb during the fish kill process. The carp’s swim bladder is connected to its throat via a tube, and the swim bladder has a weak ability to work as does the human lung. This fish does come to the surface to gulp air. I have seen them, living in stagnant water, come to the surface many times to gulp air. Also, Eli Sprenkle, fisheries biologist at Tuttle Creek State Park, says that he has never seen a garfish victim in a fish kill. Garfish have the same throat-swim bladder as the carp, and they often come to the surface to gulp air, even in well-aerated water. The gars, tough and adaptable, are one of the three very ancient fish types that occur naturally in Kansas. But, that is another story. 

Because real trouble can result when some ecological disturbance is linked with a break in the food chains for a variety of organisms, biologists and ecologists pay close attention to food chains. Witness what happened when a brutal heat wave parked, in late 2014, over the northeast Pacific Ocean and raised ocean water temperatures far above normal for most of 2015 and 2016. This cauldron cooked up an ecological chain reaction, which began with the death of much of the plankton in the Gulf of Alaska and eastern Bering Sea. Plankton is made up of those countless populations of small-to-microscopic plants and animals that form the first step in the food chains of most larger creatures that take their sustenance from the sea. A die-off of plankton would, eventually, lead to a marked reduction in the number of fish available to those many bird species that nest along oceans and live on fish from the sea. Many millions of seabirds did starve to death as a result of that particular heat wave in 2014. 

The more we study what goes on “out there,” the more we realize just how fine-tuned life really is and how tightly intertwined life cycles are — including human lives with the rest of life.