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Discovering the Galapagos Through Baby Tortoises

Photo by: Mfield, Matthew Field, (Own work) [GFDL or CC BY-SA 3.0], via Wikimedia Commons

Did you know that earlier this year researchers found baby Galapagos tortoises on the island of Pinzón for the first time in over 100 years? This is not only exciting news but a great way to introduce science concepts like: reptiles, life cycles, interdependence of species, extinction and extirpation, Darwin's theories, invasive species and conservation.

The Galapagos tortoise is an incredible creature. Its long lifespan- averaging 177 years - has been the key to keeping this species alive despite some dire circumstances in their native environment. In the mid-18th century explorers accidentally brought rats along with them on explorations to the Galapagos island of Pinzón. Like many introduced species, the rats wreaked havoc on the population of tortoises, eliminating eggs and young. The rats literally rendered the adult tortoises unable to reproduce because any time they tried their young would be eaten.

Baby tortoise and tortoise egg. By http://www.flickr.com/photos/akeg/ [CC BY-SA 2.0], via Wikimedia Commons

Conservation efforts in the 1960's spearheaded the mission to preserve the remaining tortoises and help their young to survive. The island was searched for eggs and any that were found were taken to incubate on another island. Once they were five years old and large enough to avoid becoming a rat's meal, they were brought back to Pinzón.

By David Adam Kess (Own work) [CC BY-SA4.0], via Wikimedia Commons

Unfortunately this did nothing to prevent the invasive rats from thriving on the island. Eventually, in 2012, biologists distributed poison targeted specifically at the rats, which finally helped eliminate them and restore the island more closely back to its original state.

With the rats gone, the tortoises could breed again. James Gibbs,

faculty at the State University of NY, recently led a survey on the island that revealed 10 tortoise hatchlings. Estimations based on their observation of adult tortoises show that there are now probably close to 500 tortoises on the islands.

The Galapagos are definitely intriguing with their fascinating wildlife and their history in helping to form Darwin's theory of evolution. In fact, the observation that one could identify which island a particular tortoise came from based on the shape of their shell was one of the key ideas that helped Darwin develop his theory.

By mtkopone (originally posted to Flickr as Going Places) [CC BY-SA 2.0], via Wikimedia Commons

Many lessons could be introduced using the Galapagos tortoise. From learning about reptiles, life cycles and different animals in Preschool or early Elementary to investigating invasive species, conservation and even ethics in Middle or High School grades.

Some resources and lesson plans for learning more about the Galapagos:

Classroom Resources: Books and Lesson Plans from the Galapagos Conservancy
Galapagos: Beyond Darwin, Grades 6-8 Lesson from Discovery Education
Animals, Adaptation and the Galapagos Islands: A Science Explorations Activity, Grades 3-5, 6-8, 9-12 from Scholastic and the American Museum of Natural History
Animal Diversity Web: Giant Tortoise

There are some fabulous picture books about the Galapagos tortoise and other wildlife worth taking a look at. Click the book images for more information. (Amazon affiliate links)

Ruth Heller's "Galapagos" Means "Tortoises"

A beautifully illustrated picture book written in rhyming text. A survey of the amazing wildlife on the Galapagos Islands.

Jean Craighead George's Galapagos GeorgeA story about the famous long-lived Lonesome George, one of the most rare creatures in the world. Lovely painted illustrations and a great peak into the diversity of life on the Galapagos.

Jason Chin's Island: A Story of the Galápagos

Tells the long history of these islands and their incredible creatures with scientifically accurate text and wonderful painted illustrations.

Galapagos Tortoise - Curious Kids Press: Kids book about animals and wildlife, Children's books 4-6A book of tortoise facts illustrated with photographs. (fyi: available free for Kindle if you have Amazon Prime)

Read more about the discovery of baby tortoises:

The Dodo: "Baby Tortoises Found on Galapagos for the First Time In 100 Years"
IFLScience: "Galapagos Island Hosts First Baby Tortoises In A Century"
Nature: "Giant Tortoises Hatch on Galapagos Island"

(affiliate link)

STEM Opportunities Where the Bison Roam

For a century, the wood bison have been extirpated (or locally extinct) from Alaska. That is all about the change. The wood bison, a larger subspecies of the American bison that roam places like Yellowstone National Park, are about to be re-introduced to an ecosystem that has been long missing a large grazing animal. This reintroduction project, which has taken over 20 years to complete, is not only good for Alaskan ecosystems, but also a great way to teach science and math.

This post contains affiliate links, please see disclosures for more information.

The Alaskan Wildlife Conservation Center (AWCC) has been working with the Alaskan Fish and Game Department to bring back this species, whose status changed from endangered to threatened in 2012. Sunday March 22nd, 2015 the Alaska Department of Fish and Game began the process of moving the animals from the conservation center where they have been raised to a staging area where they will then prepare for release.

The bison were flown in 20 foot containers that have 7 individual stalls to carry adult bison, each weighing anywhere from 1,200 to 2,000 lbs. The containers can carry up to 17 of the smaller, juvenile bison. The first introduction will be females, of which about 25 are pregnant, and juveniles 2 years or older. Males will be brought in by barge in the summer. In 2-3 weeks when they have acclimated to the staging area and are shown to be in hearty and healthy, they will be released into the wild.

The project has taken time because of red tape and restrictions. An agreement has been reached and this population of bison is being considered an "experimental population not essential to the continued existence of the species" and will be maintained by local wildlife officials. This consideration allows the bison to be exempt from the restrictions of the Endangered Species Act.

In order to educate students about this project, the AWCC, Bear Trust International and Inspired Classrooms teamed up to create free STEM curriculum surrounding the wood bison release. The curriculum targets students in grades 7-8 and meets Alaska and National Science Standards. This STEM oriented lesson has students studying real data and developing their own management recommendations based on calculations of how much wood bison eat, the size of available sites, land ownership issues and more. The curriculum can be found on the AWCC website here. Additional lesson plans cover wood bison behavior and the natural history of other Alaskan ungulates, or hoofed animals.

This project is a great opportunity to not only teach about the science and math of species management, but also many other interdisciplinary concepts. Food webs, population maps and geography, land history, federal regulations and legislation, etc. How do you envision using a topic like this in your classroom or home study? Leave your ideas in a comment below, or e-mail me at shareitscience@gmail.com

Post updated: 4/14/16

Read more:

US News and World Report: "Planes, trucks and boxes: Alaska preps for return of 2,000-pound wild wood bison, gone century"
Alaskan Wildlife Conservation Center: "Wood Bison Restoration Project"

Project Resources:

Here are some additional resources for your study of Bison and Alaskan Wildlife. Click on the images for more information.

It's Raining Acorns!

It seems like this year is a good one for the oaks. The past few days I have literally heard acorns raining down in the forest around my yard, and they are littering walkways and sidewalks everywhere. I am sure many in my neck of the woods remember the exceptionally big "mast" year for acorns- 2010. That year it was a painful proposition to take a walk under an oak tree, they rained down for days. Mast is the word used for the reproductive part of woody plants, in other words, the seeds of trees and shrubs. There are soft masts and hard masts. Soft masts include tree buds, catkins and berries, whereas hard masts-you guessed it- are harder "fruits" such as acorns, hickory nuts and beech nuts. In some seasons there are more hard masts, like acorns, produced than others. It is a phenomena that scientists have difficulty predicting with great certainty, although there can be some predictable factors such as weather. Like all things in nature there are so many causes and interconnections that predicting a good mast crop year is a little tricky. These abundant years could happen two years in a row, or may have two to five years in-between. Weather may be a factor, however, since most acorns or nuts are on a two-year growth cycle, the weather that is advantageous for producing a larger quantity of seeds may occur in the year before we notice the seed production.

As you can imagine, more acorns means good eating for herbivores such as chipmunks, squirrels, turkey and deer. Squirrels not only have a lot to eat, but they also help the tree to disperse its seeds. Gray squirrels bury their acorns in a variety of different places and then only recover some. These forgotten seeds often grow into saplings. In essence they are planting the seeds for the oaks.

Gray squirrels are smarter than you might think when it comes to acorns. Scientists have found that the squirrels can differentiate the acorns from white oaks and the acorns from red oaks. The white oak seeds germinate very quickly, and therefore lose their nutritional value hastily. The squirrels eat these first, rather than store them for later. They prefer to store the red oak acorns to eat over the winter and spring. Even more incredibly, sometimes the squirrels will bite through the embryo of the white oak acorns, prohibiting them from sprouting. This makes the white oak acorns just as valuable to store as the red. The wonders of nature never cease to amaze- if only they could evolve the behavior to look both ways before crossing the road!

Obviously, there are pros and cons for many natural phenomena, depending on your species and perspective. Scientists have linked larger Lyme disease carrying tick populations to years with small acorn crops. A good mast year in the northeast can lead to a boom in the population of white-footed mice, whereas a meager crop causes a big drop in the mouse population. White-footed mice are the preferred host for the black-footed tick which is very good at carrying and transmitting Lyme disease. When the population drops, the ticks are forced to find other hosts- including us. This was very clear after the huge mast crop in 2010. The mouse population sky-rocketed, then the following year the acorn crop was practically non-existent. The subsequent mouse population crash caused the potential for an influx of Lyme disease that year. Many believe that the tick population has only to do with the weather, but again, there are many factors at work in the complex natural world.

Regardless of the larger food web implications of raining acorns, it's probably best to duck and cover this fall if you venture out under the oak trees- they come down pretty fast!

http://newswatch.nationalgeographic.com/2014/09/26/squirrels-animals-fall-winter-science-united-states-surprising-facts/?afsrc=1

http://blogs.massaudubon.org/yourgreatoutdoors/about-those-acorns/

http://www.sciencedaily.com/releases/2012/03/120316094452.htm

Tree Activities and Resources

Mast Tree Network

http://www.mast-producing-trees.org/

Arbor Day Tree ID online field guide

http://www.arborday.org/trees/whatTree/

Arbor Day Tree ID lesson plan (grades 4-12)

http://www.arborday.org/kids/TreemazeFINAL.pdf

Project BudBurst- Citizen Science Project

http://budburst.org/