This is going to be a bit more of a laid back effort compared to my recent dual diary series on bird evolution. It was spring break this past week and my wife and I took the opportunity to explore a bit more of the state we've called home for close to three years now. This being Florida we went to the beach. Being nerdy biologists we probably didn't do what most people would do at the beach. This diary is about what we learned while visiting Merritt Island National Wildlife Refuge and Cape Canaveral National Seashore. Otherwise known as the space coast. Expect some natural history and some thoughts on on how insights into the natural world might guide us forward in thinking about our brave new world.
This somewhat smaller 'aircraft' was coming in to land about an hour before Discovery landed last Wednesday.
The refuge and the seashore site to the north of Cape Canaveral Air Force Base and the NASA facilities. Both preserves were acquired by NASA when the space center was being built and all four federal properties form a large area of mostly natural habitat in coastal central Florida.
I'm going to show a lot a pictures from my trip in this diary but I'm going to use them to make a point. Many, if not most, organisms have a pretty restricted environment in which they live and alteration of the environment by humans, especially alteration of the climate and sea level is going to have some pretty dramatic impacts.
Let's start with the beach. It is a pretty simple and uniform environment.
But you will notice a definite angle to the picture. Cape Canaveral has a pretty steep beach but in all cases the top part of a beach is going to be drier and more stable and the lower part is going to be wetter and less stable. Different organisms are going to live in different places.
Some species are both highly mobile and capable of living in fairly diverse environments. This otter was moving through an oak hammock, presumably from one body of water to another. Otters once lived across almost all of the US and Canada south of the arctic and are rapidly recolonizing areas where they once lived.
In contrast are the barnacles on this juvenile loggerhead turtle. These barnacles are specialized for living on sea turtles and are found nowhere else as adults. They are reliant on a specific environment for their existence. Incidentally the high barnacle load on this turtle probably indicates poor health.
So let's look at some of these environments.
The beach itself has few nutrients or plant life. Nutrient input is largely from the sea in the form of things washed up on shore.
This is not a jellyfish. The Portuguese Man O War is actually a colony of organisms called Hydrozoans (related to both jellyfish and corals). The blue structure is a bag of air that is used for flotation. The close up gives you an imperfect look at the different individuals (each one a polyp - a sea anemone like organism but highly modified).
Above the beach are dunes. Specialized vegetation grows in this harsh environment.
The fast-draining, nutrient poor soil and constant window make this a water poor environment. Good for plants like this prickly pear.
Older dunes far inland support similar arid-adapted plants and are home to highly specialized animals such as this Florida Scrub Jay. Many of these animals are relicts from a time when Florida was much drier than it is now and are now restricted to these islands of scrub habitat. The jays are more prone to cooperative breeding than their western relatives which appears to be a response to a very limited number of breeding territories.
Behind the dunes are lagoons and wetlands both salt and fresh. One thing I wasn't expecting (not sure why I wasn't, just hadn't thought about it) was the presence of mangroves. Mangroves are tropical trees that grow partially submerged in salt or brackish water. Mangroves have multiple evolutionary origins. Plants in several different families have evolved a common body form in response to a common environment.
Where I live in the panhandle mangroves are effectively absent (I've been told that they occur along the entire Florida coast but up here they are rare and small enough to be ecologically unimportant) and we have vast expanses of salt marsh. On Merritt Island there is both mangrove and salt marsh.
The shallow fluctuating water levels are important for a rich variety of life. It provides a haven from predatory fish for a number of small or juvenile fish species.
And conversely provide good places to forage for a wide variety of shore and wading birds.
Yellowlegs
Reddish Egret
White Ibis
At slightly higher elevations you get freshwater marshes
And hardwood hammocks
Resurrection Ferns growing on a fallen live oak
Wild coffee growing on the side of a shell mound constructed by native Americans.
The salt water necessary to the marshes and mangroves would kill most of these organisms.
How will climate change affect these systems? Rising sea levels and more frequent storms are going to push everything west. Warmer weather will allow species such as the wild coffee and mangroves that are limited by freezing temperatures to expand their ranges north. Other species may no longer be able to survive the warmer climate and will need to move north or die out.
The generalists and highly mobile species are going to be the most successful. A warming world will probably be one dominated by species that are good colonizers and can tolerate a wide range of environments. Specialists are more likely go extinct because their populations will not be able to disperse or evolve their way out of their current situation.
And now I'm going to get on my soapbox
The question to ask is: are we otters or turtle barnacles? Are we so stuck in the world we have now that we can't visualize a new one. This is an important question because, unlike the turtle barnacle we have some control over our destiny. Our ability to live and thrive in the world we've so drastically modified depends less on our ability to evolve our way out and more on our ability to imagine our way out. dkos has had a great group of environmental diarists who have been tremendously successful in generating a lot of useful information. I'm a bit worried that dkos4 has fragmented things a bit but maybe that's just me.
What I've done here is given you a very brief sketch of the world of some species and their interactions with the environment. With enough time I could flesh it out quite a bit. Environmental diarists are excellent at describing the world in which we live in and the problems that it faces be they related to energy, legislation, melting ice caps, what have you. Although we perhaps see the problems more clearly we are as stuck in the world we live in as the next person. It is all too easy to slip into a self-defeating 'ecological nihilism' to quote the esteemed laughing planet.
In the fall I exposed students to the concepts of sustainability in an honors seminar. At the end, after getting a lot of bad news, I asked them what kind of future they wanted to see. They liked this approach but didn't really have any concrete ideas. This is the central challenge of environmentalism as I see it, to take what we know and use it imaginatively to create a vision of the future.
Cape Canaveral is the site of one of the great technological achievements of our species. We need to aspire to another achievement rather than merely react with (justifiable) fear and concern to the world around us. The earth is our home, a home for which we are responsible, by virtue of both our sentience and our power.