Home Methods 1 | Photo Identification | Mark and Recapture Biopsy | Summer Feeding Areas, Wintering Grounds and Migration | Human Impact | Population Estimates
Activity 1: Questions about SPLASH | Activity 2: Interpreting Graphs | Activity 3: Mark and Recapture | Activity 4: Estimating Humpback Population Growth | Activity 5: Whale Tails: Photo ID | Activity Answers
- Activity 1: Splash in Questions
- Activity 2: Interpreting Graphs
- Activity 3: Mark and Recapture
- Activity 4: Estimating Humpback Population Growth
- Activity 5: Whale Tails Photo Identification
SPLASH IN QUESTIONS: Activity 1
1. How many square miles is the North Pacific Basin? Millions
2. What were four goals of the SPLASH research project? Determine population size, migration routes, determine summer and winter areas.
3. How many researchers were involved in this project? 400
4. What was one of the major successes of SPLASH? Scientists were able to work together for a common goal.
5. What were the large research ships used for? Offshore surveys
6. In the 1970’s, what did researchers discover about the flukes of a humpback whale? Every humpback had a unique pattern.
7. Describe what Photo ID is? A whale’s fluke is photographed and subsequently photographed at another time.
8. What is a “match”? You have a photo of a known whale fluke and photograph it again at another time. If the fluke patterns look the same, you have a “match”.
9. What is Photo ID used for? Migration, population studies, aging
10. How many photo ID pictures were taken during SPLASH? 19,000
11. How did whale biologists study whale populations prior to the discovery of Photo ID?
Discovery tag was shot into the whale and possibly recovered if it was killed by whalers.
12. What is “mark and recapture”? A method to study animal populations.
13. How is a whale actually “marked”? “recaptured”? It is marked if you take a photo of the flukes. It is recaptured if it is subsequently photographed.
14. What is a biopsy sample and how is collected? Sample of genetic material. A dart is shot into the back of the whale and the sample is recovered.
15. How do whale biologists use biopsy samples? Genetic studies on populations; migrations, gender and level of pollutants in the whale’s body.
16. In general, where do whales travel to in the winter and why? Sub tropical areas to mate and have calves.
17.Where is the main wintering area in the North Pacific? Hawaii
18.What is one reason whales tend to return to the same area each year? Inherited genetic information from the mother.
19.Why do humpbacks migrate to northern latitudes in the summer? Feed on plankton and small fish.
20. Using the map, name 3 of the summer feeding areas. Aleutians, Gulf of Alaska, SE Alaska
21.What was special about the discovery of the humpback that was photo ID’d in the Revillagigedos and the Commander Islands? It was one of the longest migrations of humpbacks ever recorded.
22. What are the Southern Hemisphere humpbacks using the waters off Central America for?
Winter, breeding and calving grounds.
23.What importance is the “match” of the Antarctic humpback that was seen off Costa Rica in 1995? It was the longest migration known and showed that humpbacks in the Southern Hemisphere swam all the way to the Northern Hemisphere.
24.What are some ways that humans negatively impact humpbacks? Hit by ships, entangled in fishing gear, pollution.
25.What is one possible reason that the Southern California humpbacks have such high levels of DDT? DDT was discharged off Palos Verdes Peninsula into the ocean.
26.What are two of the most destructive type of fishing gear to a humpback? Pots, gill nets, and seines.
1. How many humpbacks spend the winter at the Mexico Mainland? 2000
2. What is the total estimate for humpback whales on the feeding grounds? 20,000 whales.
3. Judging by the thickness of the migration line, which breeding area has the largest migration? Hawaii
4. What is the highest type of gear entanglement in the North Pacific? Crab Pots
5. What is the total amount of gill net entanglements in the North Pacific? 29 gill net entanglements
6. What region had the highest rate of entanglement? AK (Alaska) with 46 entanglements
7. In 1992, what was the population estimate for humpbacks living on the West Coast of the U.S.? 600 whales
8. What does the graph indicate about the humpback population in 1999 and 2000? The population dropped from 1998 (1000) to 700 in 1999 and 800 whales in 2000.
9. What are the two main wintering areas in the North Pacific and how many whales are estimated? Hawaii (10,103) Mexico (5,928)
10.What are three main summer feeding area and how many whales are estimated? Aleutians-Bering Sea (10,531); Gulf of Alaska (3,375); S.E. Alaska-Northern British Columbia (3,156).
11. Why are totals different for the wintering area and the feeding areas? These are calculated estimates and there is a margin of error involved.
12.Off the Russian East Coast, how many whales had two serious injuries? 4
13.What is the total number of whales that had entanglement scars in SEAK (South East Alaska)? 312+29+? = 341 whales
1. How many animals were “marked” in Survey 1? 12
2. How many animals were “captured” in Survey 2? 11
3. How many animals were “recaptured” in Survey 2? 4
4. Using the formula above calculate the number of animals in the population: 33
Estimating Humpback Population Growth
2008: 21,000 x .05 = 1050; 1050 + 21,000 = 22,050
2009 :22,050 x .05 = 1102; 1102 + 22,050 = 23,152
2010: 23,152 x .05 = 1,158 ; 1158 + 23,152 = 24, 310
2011 : 24, 310 x .05 = 1215 ; 1215 + 24,310 = 25, 525
In the five years the population is projected to be 25, 525
Whale Tails: Photo Identification
Whale c from Gulf of Alaska is Whale 6 from Maui.
Whale d from the Gulf of Alaska is Whale 5 from Maui.
Whale e from the Gulf of Alaska is Whale 4 from Maui
Whales 1,2,3 from Maui were not seen in the Gulf of Alaska.