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| You know what makes birds so neat? The answer
is that they fit so perfectly into the dynamics of the natural
community in which you see them. Indeed, they must because that is
the rule for any species of plant or animal which naturally occurs
in a particular habitat. Every species has a multitude of roles to
play from consumer to producer to reproducer and they all move
through what Storer called the "Ecological Web". The natural world
is, at once, incredibly complex with all its interacting living and
non-living components and is still remarkably simple as it always -
without outside interference - works. I have come to call it "The
Simplicity of the Complexity". When you are out there birding, try
to be aware of the amazing dynamic of natural communities and the
way in which bird species - not just individual birds - move within
that dynamic. I will share an example with you:
By the way, bats come out at night and fly-catcher type birds go roost at dusk. I bet you can figure that one out. It all has to do with the way in which natural systems tend to maximize resource utilization in such a way as to maximize the diversity of a community. And, what is the point of maximum diversity, you ask? I will ask you: why does a stockbroker tell a client to diversify his portfolio? It is the same answer: diversity promotes stability. It is as if a natural community is a very wise individual. But it is not. If not, then what? I must insert a note of caution. Birds - or any - species are not the wise ecologists they appear to be. Red-wings do not come to a marsh and decide to set up shop on the reeds one fine day no matter how neat it might look. Red-wings use the reeds because, over countless generations in countless marshes, they have become quite successful as reed masters. In fact, they have become more successful than most other bird species which may have also tried that habitat trick. To put this into a more evolutionary context, Red-wings with genetic "drives" that encourage reed use have been more successful than Red-wings with genetic "drives" for ground use. Therefore, over time, Red-wings - as a species - have become reed users. It was a complex process that required countless trial and error (mostly error) experiments and it can all be summed up in these words "what you see now is really very simple. It works." So, marvel not at the presumed intelligence of the Red-wings you see. The brain power is far more apparent than real. Marvel instead at the simple fact of success because it works so well. And, here is yet another caution: There is a risk implied with any specialization such as reed use. What do you think might happen to the Red-wing population at Peck's Lake if all the reeds were removed and marsh drained? These birds would find themselves in a habitat devoid of their highly preferred feature. Not only that, but the remaining parts of the habitat - the Mesquites and desert shrubs - are already filled up with species that have been successful in those places and will likely out-compete the Red-wings for space. Specialization can be a two-edged sword. The moral of the story is simple: conservation efforts are properly aimed, not at protecting a given species, but rather at protecting the integrity of habitats. When you are out birding, take delight at the wonderful bird species but think in terms of habitat. And, really, that's pretty simple, isn't it. |
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Peck's
Lake is an old ox-bow lake in central Arizona. On any given Spring
morning I can see Red-wing Blackbirds, Yellow-breasted Chats,
Phainopeplas, Say's Phoebes, Gambel Quail, and Black Phoebes. At
first glance it is a hodge-podge of bird species. But look closely
and you see habitat splitting at its finest. The Red-wings use the
tops of reeds on the marsh edges for display sites and nest down in
the reed cover. The Chats tend to display and spend time in the
thick middles of the Mesquite trees next to the marsh. The
Phainopeplas perch on the highest part of the tallest Mesquites and
defend territories from their lofty sites. Say's Phoebes sit on the
edges of Mesquites and spend a good deal of time making short
(highly visible) foraging flights. The Quail run around the ground
picking up seeds. The Black Phoebes live along the stream edges and
silently patrol their boundaries as they forage for flying insects.
Each of these species can place a large number of individuals at
Peck's Lake but none of them -as species - truly compete with each
other because they have partitioned the habitat so neatly. If all
these individuals "wanted" to use the tops of Mesquites for display
posts, there could be only a fraction of the existing numbers of
birds. But that is not the way it works. These birds - as species -
use only identifiable parts of the habitat. What you see is a lot of
pretty birds and that seems pretty simple, even though the
ecological reality is really quite complex.