Sea otters◆ are some of the most adorable creatures on the planet. Their heartwarming behavior and furry faces are enough to brighten the gloomiest of days. Anyone who has browsed through social media can attest◆ to that after watching videos of sea otters holding hands while they float sleepily in the water. Sea otters float on their backs even while enjoying a meal by smashing shellfish◆ against their chests. Mothers attend to their young while on their backs as well.
Holding hands is one way sea otters keep themselves from drifting away from each other, but another method is to wrap themselves in kelp◆. This can be seen when they are resting together in large groups, called rafts◆. Some researchers have spotted rafts made up of over 1,000 sea otters, an encouraging◆ number thanks to years of intervention and protection by the US government.
In the early 20th century, sea otters were on the verge of extinction, having been hunted for their thick and valuable fur. Yet, now with their numbers bouncing back, sea otters are being recognized as a keystone species◆, meaning they are crucial to maintaining healthy ecosystems◆ and the overall health of the environment. Without them, kelp forests, which absorb enormous amounts of carbon dioxide◆ and provide sustenance◆ for fish and other sea animals, would be destroyed by hungry swarms of sea urchins◆. The sea otters help keep the sea urchin population in check by consuming them, allowing kelp forests to flourish.
Researchers have noted that the influence of sea otters extends to every species within the coastal◆ marine◆ environment. It seems this species was saved just in time, not only helping to save ecosystems but also aiding our planet by decreasing carbon dioxide levels. -------------------------------------
1. Which of the following is NOT an activity sea otters do while floating on their backs?
(A) Rest in rafts.
(B) Devour shellfish.
(C) Construct kelp forests.
(D) Take care of their offspring◆. -------------------------------------
2. What can be inferred from the second and third paragraphs?
(A) Researchers have found that 1,000 sea otters are needed for a diverse ecosystem.
(B) Without intervention, sea otters would have wiped out sea urchins.
(C) Sea urchins hunt fish and seabirds for food.
(D) If sea otters were gone, ecosystems would collapse. -------------------------------------
3. According to the passage, why are sea otters considered a keystone species?
(A) They were brought back from the brink of extinction.
(B) They are essential to a healthy marine ecosystem.
(C) They are able to herd◆ sea urchins for farmers to sell to restaurants.
(D) They have the ability to protect other marine species from predators◆. -------------------------------------
4. Which of the following is a finding of researchers regarding sea otters?
(A) Their rafts were discovered to be stable for humans.
(B) They live in communities of fish and other marine life.
(C) Their presence helps with slowing down global warming.
(D) They have the ability to absorb carbon dioxide.
 
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