READING PASSAGE 3
you shouldspend about 20 minutes on Questions 27-40,which are based on Reading Passage 3 below.
Reading Passage 3 has four sections (A-D). Choose the mostsuitable heading for each section from the list of headings below.
Write the appropriate numbers (Ⅰ-Ⅶ) in boxes 27-30 on your Answer Sheet There aremore headings than sections, so you will not use all of them.
1. Top Ocean Predators
2. Toxic Exposure
3. Declining FishPopulations
4. Pleasure Boating in the San JuanIslands
6. Smog in Large Cities
7. Impact of Boat Traffic
27 Section A
28 Section B
29 Section C
30 Section D
Issues Affecting the SouthernResident Orcas
Orcas,also known as biller whales, are opportunistic feeders, which means they will take a variety of different preyspecies. J, K, and L pods (specific groups of orcas found in the region) arealmost exclusively fish eaters. Some studies show that up to 90 percent oftheir diet is salmon, with Chinook? salmon being far and away their favorite.During the last 50 years, hundreds of wild runs of salmon have become extinctdue to habitat loss and overfishing of wild stocks. Many of the extinct salmonstocks are the winter runs of chinook and coho. Although the surviving stockshave probably been sufficient to sustain the resident pods, many of the runsthat have been lost were undoubtedly traditional resources favored by the residentorcas. This may be affecting the whales’ nutrition in the winter and mayrequire them to change their patterns of movement in order to search for food.
Other studies with tagged whales haveshown that they regularly dive up to 800 feet in this area.
Researcherstend to think that during these deep dives the whales may be feeding on bottomfish.Bottomfish species in this area would include halibut, rockfish, lingcod, andgreenling. Scientists estimate that today’s lingcod population in northernPuget Sound and the Strait of Georgia is only 2 percent of what it was in 1950.The average size of rockfish in the recreational catch has also declined byseveral inches since the 1970s, which is indicative of overfishing. In somelocations, certain rockfish species have disappeared entirely. So even ifbottomfish are not a major food resource for the whales, the present lownumbers of available fish increases the pressure on orcas and all marineanimals to find food. (For more information on bottomfish see the San JuanCounty Bottomfish Recovery Program.)....