Answers from the Whooping Crane Expert
Answers
from the Whooping Crane Expert
Special thanks to ornithologist Laura Erickson for providing her time and expertise in responding to your questions below. From: Saskatchewan
From: Omaha, Nebraska Q: Currently how many Whooping Cranes are there in all of the known populations? What are the best estimates of how many Cranes there were before they began to be adversely impacted by anthropogenic activities? What is the number (the restoration goal) of Whooping Cranes in the population that is needed before the USFWS can down list them to just “threatened”? A: Tom Stehn’s report regarding this years Aransas population: The 2005-06 winter for the Aransas-Wood Buffalo flock was one of disappointment. Despite the arrival of 30 juveniles including one set of twins in the fall, the total population only reached 220, an increase of 3 birds from the previous winter. Starting in December, food resources were limited and salinities were high, forcing the cranes to make daily flights to fresh water to drink. One 28-year-old male and 5 juveniles died during the winter, leaving the population at 214 in the spring, 2006. This was one bird less than the previous spring. In the wild, there were also 59 birds in the introduced non-migratory Florida population that was established beginning in 1993, and 64 birds in the introduced flock that migrates between Wisconsin and Florida; that makes a total of 337 birds in the wild. There are also 135 birds in captivity, not counting birds that have hatched already this year. That makes a total of 472 birds. As far as the Wisconsin-Florida population, the goal is to have 125 birds in Wisconsin by 2020, including 25 nesting pairs. But the species is still hanging on by a thread. The decision to de-list it will be based on the entire species well-being. There was an attempt in the 1970’s to reestablish Whooping Cranes in the West. This early attempt involved putting Whooping Crane eggs in Sandhill Crane nests, and allowing the Sandhill Cranes to raise the baby Whoopers. That plan worked great as far as successfully raising babies that learned a natural migration route. Unfortunately, the baby Whoopers all imprinted on their Sandhill Crane parents, and when it came time to breed, they only seemed willing to accept Sandhill Cranes for mates. Meanwhile, of course, all the Sandhill Cranes had also been raised by Sandhill parents, so NO cranes would accept a Whooper for a mate except for one Sandhill. That pair did raise a hybrid baby, but the entire family was lost in a storm. The rest of those Whoopers have all died out now. Q: Historically I understand that cranes used to also inhabit Idaho and used the Western flyway. It would seem to make sense to further disperse the population so a catastrophic event or disease couldn't wipe out most of the population. Why isn't the USFWS establishing another population that would use the western flyway and winter in Mexico? A: You are absolutely right that it’s important to disperse the population. The problem is that we’re still ironing out the best techniques for reestablishing cranes. It isn’t easy to start a population because the birds must learn their migration route from their parents (or foster parents in an Ultralight). And reintroducing cranes has proven to be extremely expensive and labor-intensive. I’m sure there simply won’t be any funding for starting another population until this project proves successful. That will be known after the birds are nesting and raising their young successfully. Right now prospects are excellent! But even if this group grows well, finding funding to establish a western population will be difficult when so many other endangered and threatened species also need help. And with changing weather patterns and increasing human populations contributing to ever increasing pressures on water resources in the West, prospects for cranes there are lower than where the climate is wetter. Q: Are there any critical habitat limitations that are adversely impacting
population recovery? If yes, what are the limitations, where are they
occurring and how
many birds could the known habitat sustain if something is not done to
improve it?
From: Maryland During
migration, power lines are
a danger. Ensuring that there are plenty of clean wetlands
is just as important. When cranes get exhausted while
migrating, they need
to see
good places
to come down. I am most concerned about their wintering
grounds. The Aransas National
Wildlife Refuge is SO vulnerable when there is little
rain. This
winter five cranes died when water levels were low and
blue crabs were in short
supply. As
people continue to draw more and more water out of the
rivers feeding the Refuge, cranes will have bigger and bigger problems.
What can
WE do about
that? Water
conservation by everyone will make the world better for
birds
AND for humans. And the more the government can do to
promote water
conservation
and to
protect wetlands, the better for everyone, too. How
to Use FAQ's About Journey North Species
Since 1995, experts have contributed answers to students' questions about each Journey North species. These questions and answers are archived in our FAQ's (Frequently Asked Questions) section. You can use today's Answers from the Expert above, along with those from previous years, in the activities suggested in the lesson, "FAQ's About Journey North Species."
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