Mom & Me: A Polar Bear Survival Story Grade Level: Grades 4-8 Time: Power Point: 15 minutes. © BJ Kirschhoffer Activities 1 and 2: Two 50-minute class periods. plant in the female’s uterus (delayed im- ger fasting period for polar bears. Less Materials plantation) until early fall, after she has time on the ice to hunt will lead to the gained sufficient weight for a successful inability of females bears to gain ample For Activity 1: pregnancy. This delay gives her time to weight for successful pregnancies, thus ❐ Copies of Mom and Me: A fatten up on seal blubber. Females of- prohibiting the species’ ability to sus- Polar Bear Crossword Puzzle ten gain more than 400 lbs. during their tain itself. ❐ Computers with Internet short hunting season, allowing them to access (or copies of mini- fast for up to eight months. posters) Teacher Prep Notes ❐ Pencils and erasers Female polar bears enter their materni- By reading the background informa- ty dens by mid- to late-October and give tion, students should recognize the For Activity 2: birth between November and January. connection between polar bear sur- ❐ Copies of Graph A (Break-up They spend the next few months nurs- vival and sea ice. This lesson contains Dates 1979-2007) ing their cubs up to six times a day several activities. All activities will take ❐ Copies of Graph B (Lone and remain in their dens through 1-2 hours. Print the Mom and Me: Female Body Mass, 1980- March or April to protect their cubs A Polar Bear Crossword Puzzle PDF 2007) from the coldest temperatures of win- and mini-posters from the Polar Bears ❐ Copies of Polar Bear ter. Newborns are 12 to 14 inches long International (PBI) website: Ecoregions Map (optional) (30–35 cm) and weigh little more than polarbearsinternational.org/education/ one pound (0.5 kg), but grow rapidly educational-tools-and-materials. Also from their mother’s rich, 33%-fat milk. print Graphs A and B (Break-up Dates Key Words When the family group finally emerges 1979-2007 and Lone Female Body Addressed in Mom and Me: A from its den, the mother stays nearby Mass, 1980-2007) and the Polar Bear Polar Bear Crossword Puzzle until her cubs develop the strength to Ecoregions Map. Familiarize yourself walk long distances. Mothers can then with the PBI website addresses identi- break their long fast and lead their cubs fied in the lesson. Use the questions Objective onto the ice to hunt seals. listed in Activity 2 to create a worksheet for students to analyze graphs A and B. Students will learn about the connec- Solid food comes when cubs are three tion between mother polar bears and or four months old and the mother cubs through an interactive explora- makes her first kill of the spring. Ringed tion of the Polar Bears International seals—the primary food source of the website. Students will also discover the polar bear—rest at breathing holes, connection between polar bear survival cracks, or on the surface of the ice. The and sea ice. They will analyze this con- mother’s success at hunting is both crit- nection through a graph analysis activ- ical for her own needs and for modeling ity, comparing two graphs—one show- the hunting behavior her cubs will need ing female polar bear weights and the to learn to find food for themselves. other showing sea ice coverage. As long as there is sea ice, these areas are also accessible to the polar bears. Background Information Although there has always been loss of Female polar bears prepare to raise sea ice during the warmest months of the year, the current overall decrease their young long before they give birth. © BJ Kirschhoffer Mating takes place on the ice in April or in sea ice and the early break up and May, but the fertilized egg will not im- later freeze up is translating into a lon- www.polarbearsinternational.org | POLAR BEARS INTERNATIONAL 1 Activity 1: Polar Bear Crossword Puzzle H D 3P To Do: 4 B L U BBER 5 B L AC K 1. Have students watch the All M L P About Polar Bears PowerPoint 6 appropriate to their grade level A A I I for an engaging introduction 7MATERNITYDEN8 L C to the polar bear world (polar- WS E L E bearsinternational.org/education/ O educational-tools-and-materials). D A F 9 1. Give each student a copy of Mom RINGE D SEALS 10 11 and Me: A Polar Bear Crossword COYS M O Puzzle. Have students explore the U P E Polar Bears International website B L 12G (www.polarbearsinternational.org/ 13 polar-bears/faq) to complete the O A A E puzzle. N D N S 14L 15 1. If students do not have Internet E U T THREE access, photocopy the mini- P L A A A posters to use in pairs or small T T T groups to complete the puzzle. O D 16 You may find mini-posters at: URSUSMARITIMUS www.polarbearsinternational.org/ N O O polar-bears/faq 17DEBBY 18NINETNEE Across Down 4 Polar bears do not have this, but they eat it. 1 The polar bear’s only enemy. 5 The color of a polar bear’s skin. 2 Used in reproduction to time the birth of cubs during the most favorable conditions for survival 7 A snow cave where cubs are born cubs (two (two words). words). 3 Small bumps that keep polar bears from slipping 9 Polar bears’ favorite food (two words). on ice. 10 What cubs are called. 6 A flat sheet of ice floating in the sea (two words). 15 Number of months a female polar bear stays in 8 Number of cubs a polar bear mom tyipcally has. the den to give birth. 11 What polar bears are called after they leave their 16 The species name for “polar bear” (two words). mothers between the age of 2 to 2-1/2 years old. 17 A zoo bear that lived to be 42 years old! 12 What the period of time a female polar bear is 18 Number of different bear populations in the pregnant is called. Arctic. 13 The weight of a newborn cub (two words). 14 Openings in the sea ice. www.polarbearsinternational.org | POLAR BEARS INTERNATIONAL 2 Mom & Me: A Polar Bear Crossword Puzzle 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Across Down 4 Polar bears do not have this, but they eat it. 1 The polar bear’s only enemy. 5 The color of a polar bear’s skin. 2 Used in reproduction to time the birth of cubs during the most favorable conditions for survival 7 A snow cave where cubs are born cubs (two (two words). words). 3 Small bumps that keep polar bears from slipping 9 Polar bears’ favorite food (two words). on ice. 10 What cubs are called. 6 A flat sheet of ice floating in the sea (two words). 15 Number of months a female polar bear stays in 8 Number of cubs a polar bear mom tyipcally has. the den to give birth. 11 What polar bears are called after they leave their 16 The species name for “polar bear” (two words). mothers between the age of 2 to 2-1/2 years old. 17 A zoo bear that lived to be 42 years old! 12 What the period of time a female polar bear is 18 Number of different bear populations in the pregnant is called. Arctic. 13 The weight of a newborn cub (two words). 14 Openings in the sea ice. www.polarbearsinternational.org | POLAR BEARS INTERNATIONAL 3 Activity 2: Polar Bears Need Sea Ice! Graph Analysis 1. With your students, define, discuss and locate ❐ List several ways this earlier ice break-up sea ice on the Polar Bear Ecoregions Map. negatively affects polar bears. 2. Look at Graph A, Break-Up Dates 1979-2007. a. Polar bears hunt ringed seals from the As a group, ask students to make observations sea ice. Earlier break-up means less and share what they notice in Graph A. Consider hunting time. creating a worksheet that includes some of the b. Less hunting time means bears are following questions: unable to gain the weight they need for ❐ In 1980, about when did the ice begin to their winter fast. break up? (Answer: June 30) c. Weight gain for females is essential ❐ In 2005, when did the ice begin to break up? because they are hunting both for (Answer: June 18th) themselves and their cubs. ❐ Is the ice breaking up sooner or later each d. Earlier ice break-up means bears are year? (Answer: Sooner) losing their habitat and coming ashore ❐ What do you think may be causing the ice to earlier, potentially creating a human/ break up earlier each year? wildlife conflict. GRAPH A: BREAK-UP DATES 1979-2007 13-Jul 6-Jul 29-Jun 22-Jun 15-Jun Date of sea ice break-up Date 08-Jun 01-Jun 1980 1985 1990 1995 2000 2005 2010 Year Date of break-up of the sea ice used by the Western Hudson Bay polar bear population, from 1979-2007. (From Stirling and Lunn 1999 and Lunn and Stirling unpublished data). 3. Look at Graph B: Female Polar Bear Body Mass, ❐ What was the average weight of a female 1980-2007. This graph shows a steady decline polar bear in 1980? (Answer: 300kg) in average female polar bear body mass and ❐ What was the average weight of a female weight over time.