PLAYA GRANDE, COSTA RICA? This resort town was long known for Leatherback Sea Turtle (棱皮龟) National Park, nightly turtle beach tours and even a sea turtle museum.However, on a beach where dozens of turtles used to nest on a given night , scientists spied only 32 国leatherbac,ks all of last year.
With leatherbacks threatened with extinction (灭绝), Playa Grande's turtle museum was abandoned three years ago and now sits among a sea of weeds.And the beachside ticket office for turtle tours was washed away by a high tide in September."We do not promote that 'as a turtle tourism destination anymore because we realize there are far too few turtles to please,” said Alvaro Fonseca, a park ranger (管理员).
Even before scientists found temperatures going up over the past decade, sea turtles were threatened by beach development, drift net fishing and Costa Ricans' interest in eating turtle eggs.Btu climate change may cause the most serious harm to an animal that has lived in the Pacific for 150 million years.
Sea turtles are sensitive to numerous effects of warming.They feed on reefs, which are dying in hotter seas.They lay eggs on beaches that are being covered by rising seas and more violent waves.
More uniquely their gender (性别)is determined, not by genes but by the egg's temperature during development.Small rises in beach temperatures can result in ail-female populations, obviously problematic for survival.If the sand around the eggs hits30 degrees Celsius, the gender balance shits to females: at about 32 degrees they are all female.Above 34, you get boiled eggs.
On some nesting beaches, scientists are artificially cooling nests with shade or irrigation and trying to protect broader areas of coastal property from development to ensure that turtles have a place to nest as the seas rise.
Why does the resort: town stop promoting its turtle tourism?
A.It decides not to disturb the turtles' normal life. |
B.Tourists have lost interest in watching turtles. |
C.There are only very few turtles now. |
D.The turtle museum was destroyed by a high tide. |
Which of the following is the major factor in the turtles endangerment?
A.The local's eating habit. | B.Drift net fishing |
C.Beach development | D.Global warming |
We learn from the last paragraph that scientists ____.
A.are doing research on the sea rise. |
B.are moving turtles to new homes |
C.are protecting turtles' nests |
D.are getting rid of sea weeds. |
The passage intends to ____.
A.introduce a special kind of sea turtle |
B.explain the mystery of turtles' eggs |
C.show the dangers a certain kind of turtle is facing |
D.attract more visitors to a sea turtle museum |