NZ Biology: The reptiles
The reptiles
This group of Meet the Locals videos highlight our rare skinks including New Zealand's biggest lizard, the chevron skink. We also focus in on the jewelled gecko and the tuatara.
You'll use the Meet the Locals videos below. Find them on your Meet the Locals DVD or on the DOC website. The links is provided in the unit.
- McRaes Flat Skink
- Chevron Skink
- Duvaucel's gecko
- Jewelled Gecko
- Tuatara
- Tuatara Release
Skinks and geckos are fascinating little animals but remind your students it's forbidden to keep any animal from the wild. Anyone interested in keeping New Zealand lizards must obtain a permit from their nearest branch of the Department of Conservation and then be in contact with someone who already has geckos and skinks and has some spare ones to give away.
For further information
The New Zealand Herpetological Society is
well worth checking out.
Years: 7, 8 and 9
Levels: 3 and 4
Science Achievement objective
Living world
Students will:
(Ecology)
Explain how living things are suited to their particular habitat
and how they respond to environmental changes both natural and
human induced.
Social Studies achievement objective
Students will:
Understand how people make decisions about access to and use
of resources.
Learning outcomes
The students will:
1. Recognise the special features of skinks and geckos and
describe them to their classmates.
2. Locate the Otago skinks habitat on a map, identify the
changes to their environment that limit their presence and match a
threat to management tool designed minimise their threats.
3. Identify the special features and adaptations of the Chvron
skink and hypothesise as to whether these features are helping or
hindering their survival.
4. Explore the likelihood of rats getting established on Great
and Little Barrier Island and design a poster or pamphlet for
boaties that gets the "no rats" message across. Plan a distribution
method too.
5. Share some research about the breeding habits of the
jewelled gecko and hypothesise in pairs as to how these features
can help its survival.
6. Examine the adaptive features of jewelled geckos and
incorporate these features in an action pastel and dye
artwork.
7. Construct a lizard friendly environment at home or school
and photograph it for others to see and learn from.
8. Examine the tuatara hatching and raising programme at
Victoria University and list items needed if they were part of the
team for the very first egg recovery and raising operation.
9. Write a diary that illustrates the Head Start process from
collection, to incubation, hatching, rearing and release.
10. Use de Bono's coloured hats to assess strategies designed
to protect the tuatara and build populations on their
islands.
Teaching and learning activities
Starter
1. Is it a fish, amphibian or reptile? Check your students'
knowledge with
Where do we fit? This is an activity for
pairs or small groups.
Answers:
- Fish - 4,5,10 sharks trout, eels, rays, kahawai, lampreys and catfish;
- Amphibians- 3,5,6,7,8 frogs, toads, axolotls;
- Reptiles- 1,2,5,9 dinosaurs, turtles, tortoises, tuatara, lizards, snakes and crocodiles.
2. Is it a skink or gecko? Jigsaw using the Skinks and geckos fact sheet found on this DOC site. Print out and cut up the fact sheet so that groups can become experts on one of the following:
- The differences between skinks and geckos and where they are found
- Skink facts
- Gecko facts or
- Threats facing our lizards.
When each group has gathered their knowledge the members move to other groups to share their expertise.
Now watch the video Duvaucel's gecko You'll see the differences between geckos and skinks with New Zealand's biggest gecko as a model. Students will also see how the area's wildlife had to respond to environmental changes.
3. Otago's skinks
A Changing Habitat for Otago's Skinks shows
students just how much the environment changed and why it
changed.
Check out a map to see where lizards used to live compared to now and then after watching the Macraes Flat video try the adaptation activity.
These Facts about grand and Otago skinks should help as will the three below.
- These giants are only found in Otago where they are active in
the sunshine and live among deeply creviced schist rock outcrops in
montane tussock grassland.
- The two species are seen together at some sites but Otago
skinks are found more often on extensive rock bluffs along
steep-sided valleys. The grand skinks are more common on ridge-top
rocky pinnacles.
- They usually stay around their rock surfaces but both species sometimes make long trips between habitat patches - up to 400m for grand skinks and 2km for Otago skinks.
4. The endangered classification for these skinks is nationally
critical and population modelling once suggested "functional
extinction" of both species by 2010.
Management programmes utilise a range of tools and Minimise the threat has students matching each threat to a management tool and deciding how it can help the skinks survive.
5. The chevron skink
This skink is New Zealand biggest lizard and is only found on
Little Barrier and Great Barrier Islands. Historical records show
this skink was once on the mainland but Norway rats helped clean
them out. Both animals like to occupy the same habitat but Rattus
norvegicus, are quick to eat their flatmates.
Watch the Meet the Locals video
Chevron Skink taking
special note of how secretive and well camouflaged these lizards
are. Look closely at the skinks' preferred habit and the teenager
without a tail.
After the video, think, pair and then share ideas in class for the
question:
Why do lizards lose their tail?
Answer:
- Lizards have throwaway tails to escape from predators.
- Nervous spasms make a newly dropped lizard tail wag around as if it's alive.
- This headless twitching "animal" startles predators and in the confusion the lizard escapes - minus a tail but often unharmed.
- Original tails are made of bony vertebrae but the shock of the loss jumpstarts cells to build new tail out of cartilage.
- Tail building uses up a lot of energy and as lizards get older their tails actually become less colorful and less attractive to predators.
- Geckos like the jewelled gecko climb around in trees and use their tail like another leg. They will drop their tail if necessary but the one that grows back is never as long or as handy as the original.
- Lizards store their food in their tails so if they drop off in winter when there is less food around they could be in for a hard time.
Niho Taniwha - the chevron skink looks at the
special features of the chevron skinks and in pairs students can
decide whether these features are helping or hindering their
survival. Each pair can share ideas with another pair before
reaching a class agreement.
6. The rats are laughing focuses in on Norway
rats and the possibility and consequences of these predators
getting established on Little and Great Barrier Islands. There's
every chance the rats would wipe the chevron skink out as the
crafty rodents would slink along the same damp pathways.
Get your students to read the information on
The rats are laughing but before they design
their pamphlet or poster try this retrieval exercise in groups.
| The groups | could take this action | for this purpose | and the impact on the
chevron skins would be |
| DOC | |||
| Local residents | |||
| Boaties | |||
| Visitors |
7. The jewelled gecko
Share these points with your students and decide which ones are
problems that could be wholly or partly solved.
- The jewelled gecko is endemic to New Zealand, so it's the only
place it occurs naturally.
- Jewelled geckos live in the south-eastern part of the South
Island, east of the Southern Alps and from mid- Canterbury south to
Stewart Island. The biggest populations live on Banks Peninsula
near Christchurch and the Otago Peninsula near Dunedin.
- Loss of habitat is the biggest threat, followed by rats and
other introduced predators. Most of the habitat loss comes with
clearing of forest and scrubland for farms.
- Because of the slow breeding rate, gecko populations are slow
to recover in regenerating forests, and sometimes never do.
- This attractive gecko is also appealing to the illegal pet
market.
- Jewelled geckos are masters of camouflage and are very
difficult to find.
- DOC classifies these geckos as a threatened with humans
responsible for their gradual decline.
Watch the video Jewelled Gecko and look closely at the adaptations this lizard has that help protect it.
Find out too what Shirleen Helps, the woman in the video has done on her farm to protect these little lizards.
8. Share the information below with your students and then try the think, pair and share questions.
- Jewelled geckos breed annually. They mate in September and October and give birth in May or June. Gestation is usually 8 to 9 months but geckos can delay fertilisation.
- New Zealand geckos are the only ones in the world to give birth to live young but the birth process is a little different to most mammals. The baby geckos develop in the eggs which remain in the oviduct until they hatch prior to birth.
- Geckos usually have twins and each one is nearly half the length of the mother at birth. The young stay with their parents, but the parents don't really look after them. They fend for themselves!
Think, pair and share your ideas.
(a) Which of the features just described, help this lizard
survive?
(b) Why do geckos in New Zealand give birth to live young when
geckos in other countries hatch from eggs?
Answers:
(a) Adaptive features include:
- breeding annually so the population is topped up
- delaying fertilisation may happen when the food supply is low
- and the geckos' size at birth helps them look after themselves.
(b) Researchers think the live births are most likely due to the need to keep developing geckos warm in the cool climate.
9. These ten
amazing photos of jewelled geckos
are well worth looking at.
Again, check out those adaptive features:
- Markings that let them hide in the shadows of leaves
- Long clawed toes to climb
- A long tail to hang wrap around branches (The replacement is never quite as good as the original so they don't drop tails as readily as skinks.)
- Loose and grainy skin
- A body that lets them lunge quickly at prey
- A mouth that lets them catch their prey.
Jewelled gecko asks students to show these adaptations in an artwork. Pastel and dye is good but crayon and dye will be just as effective.
The adaptations are listed in boxes under separate headings and the idea is to include something from every box in the picture. Strive for a picture that gives information without words.
Handy hints:
- It's an action picture. It's a lizard on the go in its habitat!
- Draft out the sketch first in pen on an A5 piece of paper.
- If the gecko is tiny draw a box around it and tell your student to blow that bit up big.
- Sketch your drawing on cartridge paper using chalk or a light crayon. Don't use pencil because time will be spent drawing fine bits that can't be replicated with crayon or pastel. Students will also spend more time rubbing out than thinking about their art.
- When using crayon or pastel put a thick wad of newspaper under the cartridge for a better texture.
- Colour from the inside out and avoid lines around shapes. Only colouring in books have those.
- Look for detail in the gecko and surroundings. Bring in some likely plants for observation.
- Most of the artwork should be in crayon or pastel. The dye will be the highlight.
- The bigger the better - A3 at least!
10. Bring in the lizards describes ways of attracting lizard to gardens. The students could try the ideas at home or if you have a likely area at school, adapt the ideas for a lizard lifestyle at school.
Lizard friendly gardens and homes are easy to make and can make a difference. The little reptiles will hide and escape from the cats! If your students do make a lizard home in their backyard get them to photograph it for others to see.
11. Tuatara
This living fossil has hardly changed from the dinosaur days 220
million years ago but life's been tough since humans and their rats
arrived. Tuatara were once found all over New Zealand but now they
only live on offshore islands. It was one of the first species to
be protected by law and that was in1895.
Karori Sanctuary Trust in Wellington has them - the first wild
(or semi-wild) population to be established on the mainland since
they became extinct over 200 years ago.
The last of the reptile videos looks at the programmes aimed at
keeping tuatara in a healthy state. After all, their Order
Sphenodontia , was represented by many species during the
age of the dinosaurs but they all became extinct about 60 million
years ago. Except that is for old tuatara!
Tuatara are reptiles but not lizards. Their skull, ribs, teeth, the
third eye and the way they mate makes them different. Get to know
the tuatara with the
Tuatara Trust. Click on
Fun for kids and check out the special features of
tuatara as a class. In groups decide:
- Which features are similar to the lizards that you have got to know?
- Which features are completely different?
- Which features might have helped it out survive other species from the dinosaur days?
- Which features made tuatara easy prey for introduced mammals?
http://www.tuataratrust.co.nz/facts.htm
http://www.tuataratrust.co.nz/education.htm
12. Now watch the first
tuatara video You'll find out
about the Head Start programme at Auckland zoo which is a little
like Operation Nestegg for the kiwi.
Have the students consider this question as they watch:
What makes the tuatara such a good animal for a research, breeding
and relocation programme like this?
13.
Tuatara babies examines the hatching and raising
programme at Victoria University.
As an activity the students are asked to list the things they would
need if they were part of the team for the very first expedition to
the islands to collect eggs and what they'd need to raise the
tuatara back in Wellington. They then write a diary that shows the
progress and tasks from collection, to incubation, hatching,
rearing and release.
14. Share this information about tuatara eggs in the wild:
Laying months: October/November.
Nesting place: Open areas in nesting
rookeries.
Nest type : Little chambers or blind
tunnels.
Mum's job: Build the nesting tunnel and fill
it with loose soil. Lay the eggs, leave and don't return.
Incubation: 12 to 15 months depending on the
temperature.
Hatching success rate: 40% compared to 80% in
the laboratory.
Now that the students know about hatching eggs in the laboratory see if they can come up with a plan, or piece of equipment for increasing the hatching success rate of eggs left on the islands.
Ponder this!
The adult male/female hatching ratio can get skewed and end up with
a population that includes a lot more males than females. A change
in temperature of even one degree may determine the baby's sex. In
an incubator, 18 degrees produces females while 22 degrees hatches
mostly males.
There's a worry that global warming will contribute to a male
dominated population. You may need to give your students this handy
hint before they embark on their hatching scheme.
15. The second video looks at a tuatara release on Cuvier
Island.
Many of these rat free islands have very little forest to provide
compost and food for earthworms, slaters and soil insects. Seabirds
do the job instead.
Bird droppings and dead leaves are dug into the soil by burrowing
seabirds. Thousands of seabirds help the tuatara by building the
rich soil for plants to grow in and for invertebrates to make their
homes.
In pairs get the students to design a diagram that shows a food
chain on rat free island made up of these things:
- forest birds,
- seabirds,
- lizards,
- tuatara,
- spiders,
- insects,
- earthworms,
- slaters,
- weta,
- beetles,
- seabird manure
- plant life.
- Now introduce rats to the island and ask, "How might your diagram change?"
15. Use de Bono's coloured hats, (explained below) before
watching the
Tuatara release video. This
video shows the next stage in repopulating the islands with
tuatara. It's a good preparation for the final activity.
Explain the young tuatara are about to be released on an island. In
groups put on the:
- White hat and decide what we need to know.
- Yellow hat and decide the good points about the idea. What are the benefits?
- Black hat and decide if there are any bad points that mean it may not work.
- Red hat and take a guess. What do you think might happen?
Now watch
Tuatara release
16
Tuatara strategies is the final activity.
Students use the coloured hats to assess strategies designed to
protect the tuatara and build populations on their island. Share
these ideas in class to finish the unit.
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