Scientists say baby sharks are at risk of being born smaller and without the energy they need to survive because of warming oceans from climate change.
Scientists studied epaulette sharks, which live off Australia and New Guinea. They found that warmer conditions expedite the sharks’ growing process. That meant the sharks were born earlier and very tired. The findings could be used in the study of other sharks, including those that give birth to live young.
The scientists studied 27 sharks. Some were raised in average summer water temperatures, about27 degrees Celsius. Others were raised in higher temperatures around 29 degrees Celsius and 31 degrees Celsius. They found that the sharks raised in the warmest temperatures weighed much less than those raised in average temperatures. They also showed reduced energy levels.
Epaulette sharks can grow to a length of about one meter. Their name comes from large spots on their bodies that look like decorations on some military clothing.
One study this year found that worldwide numbers of oceanic sharks and rays dropped more than70 percent between 1970 and 2018. Overfishing is a main concern, while climate change and pollution also threaten sharks.
Carolyn Wheeler is a doctoral student at the University of Massachusetts Boston and with the ARC Centre of Excellence for Coral Reef Studies at James Cook University in Australia. She is the lead author of the epaulette shark study. She said that while all the sharks survived, those raised in warmer temperatures were not strong enough to survive for long in the wild.
She added that if the sharks are born smaller than usual, they are probably going to have to start looking for food sooner, and they’re going to have less time to adjust to their surroundings.
The study should serve as a warning to ocean governing agencies that careful management is needed to prevent the loss of more sharks.
【小题1】What does the underlined word “expedite” in paragraph 2 mean?| A．Accelerate. | B．Slow. | C．Cause. | D．Influence. |
| A．By studying former data. |
| B．By tracking sharks in the wild. |
| C．By collecting information about climate change. |
| D．By comparing sharks in waters of different temperatures. |
| A．They are named after a military officer. |
| B．They can’t adapt to new surroundings quickly. |
| C．They are dying mainly because of climate change. |
| D．They would die soon after birth in warmer temperatures. |
| A．The reasons for sharks’ loss. | B．The measures to preserve sharks. |
| C．The function of the government. | D．The warnings about the endangered sharks. |
