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Register : an officer of an educational institution responsible for registering students, keeping academic records,

Habitat : n. habitation, dwelling-place; environment, surroundings, place in which an animal or plant naturally grows or lives

Habitationn. act of occupying a place of residence; residence, place where one lives

Habitantn. one who inhabits, one who lives in a certain place

Inhabitationn. act of living or residing in; state of being inhabited

Inhabitv. occupy, live in, dwell in, reside in; populate

Inhabitant n. resident, tenant, occupant, one who lives in a particular place

Narrator Narrator Narrator
Listen to part of a lecture in an environmental science class.
Professor Professor Professor
Now, we’ve been talking about the loss of animal habitat from housing developments, uh …,
growing cities – small habitat losses. But today I wanna begin talking about what happens when
habitat is reduced across a large area. There are, of course, animal species that require large
areas of habitat, and some migrate over very long distances. So what’s the impact of habitat loss
on those animals – animals that need large areas of habitat?
Well, I’ll use the humming birds as an example. Now you know a humming bird is amazingly
small, but even though it’s really tiny, it migrates over very long distances, travels up and down
the western hemisphere – the Americas, back and forth between where it breeds in the summer
and the warmer climates where it’s spent the winter.
So you would say that this whole area over which it migrates is its habitat because on this
long-distance journey, it needs to come down to feed and sleep every so often, right? Well, the
humming bird beats its wings – get this – about 3 thousand times per minute. So you think, wow,
it must need a lot of energy, a lot of food, right?
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Well, it does. It drinks a lot of nectar from flowers and feeds on some insects, but it’s
energy-efficient too. You can’t say it isn’t. I mean, as it flies all the way across the Mexico Gulf, it
uses up none of its body fat. But that doesn’t mean it doesn’t need to eat. So humming birds
have to rely on plants in their natural habitat.
And it goes without saying, but the opposite is true as well, plants depend on humming birds too.
There are some flowers that can only be pollinated by the humming birds. Without its stopping
to feed and spread pollen from flower to flower, these plants would cease to exist.
But the problem, well, as natural habitat along these migration routes is developed by humans
for housing or agriculture or cleared for raising cattle, for instance, there is less food available for
migrating humming birds. Their nesting sites are affected too, the same by the same sorts of
human activities. And all of these activities pose a real threat to the humming bird population.
So help them survive, we need to preserve their habitats. And one of the concrete ways people
have been doing this is by cleaning up polluted habitat areas and then replanting flowers, um,
replanting native flowers that humming birds feed on.
Promoting ecological tourism is another way to help save their habitat. As the number of visitors,
eco-tourists who come to humming bird habitats to watch the birds, the more the number of
visitors grows, the more local businesses’ profit, so ecological tourism can bring financial rewards,
all the more reason to value these beautiful little creatures in their habitat, right?
But to understand more about how to protect them to support the humming birds the best we
can, we’ve got to learn more about their breeding, nesting sites and migration routes, and also
about the natural habitats we find there. That just helps us determine how to prevent further
decline in the population.
A good research method, a good way to learn more, is by running a banding study. Banding the
birds allows us to track them over their lifetime. It’s been a practice that’s been used by
researchers for years. In fact, most of what we’ve known about humming birds comes f rom
banding studies, where we capture a humming bird and make sure all the information about it,
like its weight and age and length, are all recorded and put into an international information
database.
And then we place an extremely lightweight band on one of its legs, well, what looks like a leg,
although technically it’s considered part of the bird’s foot. Anyway, these bands are perfectly
safe, and some humming birds have worn them for years with no evidence of any problems. The
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band is labeled with tracking number, oh, and there is a phone number on the band for people to
call for free, to report a banded bird to be found or recaptured.
So when a banded bird is recaptured and reported, we learn about its migration route, its growth,
and how long it has been alive, its lifespan. One recaptured bird was banded almost 12 years
earlier – she was one of the oldest humming birds on record. Another interesting thing we
learned is that some humming birds no longer use a certain route. They travel by a different
route to reach their destination.
And findings like these have been of interest to biologists and environmental scientists in a
number of countries who are trying to understand the complexities of how changes in a habitat
affect the species in it.