Wednesday, September 1, 2010

More Than You Ever Wanted To Know About Geckos

We might as well skip to the bottom line here and state the take-home message of this blog:  retired people have way too much time on their hands.

That would certainly explain why my wife and I (a former middle school mathematics teacher and a retired professor of Social Psychology) are experts on the behavior and physical traits of a lizard  -- specifically Phelsuma laticauda laticauda, otherwise known as the Gold Dust Day Gecko or, thanks to Madison Avenue advertising geniuses, "The Geico Gecko."  It would also explain how we could come to identify individual geckos with names like "Stumpy, "Flipper," "Barbie," "King," "Mona," and "Hook."

Still with me?  It's going to get worse, so you might want to go do something more productive (unless, of course, you're retired too -- or are a retired wannabe).

There are actually several varieties of geckos in the Hawaiian islands, all of them introduced or alien.  The oldest species probably came with the first Polynesian settlers about 1200 years ago, though it might have arrived here independently since gecko eggs are highly resistant to salt water (they're about the size of a small pea and have hard shells) and gecko females can reproduce on their own through pathogenesis if there are no males present.

Two varieties that visitors to Hawaii are most likely to encounter were introduced fairly recently:  the Common House Gecko (active at night, has a laughing chirp) in the 1940's and the Gold Dust Day Gecko in the 1970's (active during the day or around light sources at night). The most recent introduction in the '80's is still very rare (in fact, I haven't seen one) -- the Orange-spotted Day Gecko .  The ones we know the most about are the Gold Dust Geckos and from here on "Gecko" will refer to this type.

Geckos love to be around humans.  Humans, though, are divided in their attitude toward being around geckos.  Some find these little guys endearing, cute, and entertaining while others find them repulsive, disgusting and scary.  We are most definitely in the Gecko-Lover group, though there are limits to our affection and tolerance.  More on that later.

Stumpy enjoying some papaya juice.
 Like their name implies, Gold Dust Geckos have small golden specks on their green backs and in the sunlight these spots really light up.  Complimenting the green and gold are red splotches on their heads and backs near their rear legs.  The shape and pattern of these splotches turn out to be very distinctive, and they are one way that allows us to recognize one gecko from another.  They also are the source of some of the names we have given to different geckos.  "Hook," for instance, is a large male with hook-shaped splotch.  "Barbie" is a female with two splotches joined together so that they look like bar-bells.  (Of course, some of our neighbors have suggested that being this observant of the color splotches on lizards may be regarded as eccentric, slightly demented, or both.)

Besides red, green, and gold, our Gold Dust Geckos have turquoise bands around their eyes and turquoise toes.  Males when they are fully mature also have turquoise at the tips of their tails -- aside from the larger size of males, this is the main way you can tell a boy gecko from a girl gecko.

The tails of geckos will fall off if they are attacked by a bird, cat, or irate human.  This is a defensive maneuver meant to distract the predator with a wriggling tidbit while the gecko escapes.  The tails seem to be detachable in different lengths, and although they grow back in a month or two, there is always a faint line at the detachment location.  The regrowth pattern is another characteristic that allows individual identification.  For example, our all time favorite gecko was named "Stumpy" because her regrown tail retained a more rounded tip than usual.

Hmmm. Pearl or gecko egg???
We find geckos endearing because they are intelligent, gentle, curious creatures who will respond positively to human kindness.  When we eat breakfast on our lanai, we are routinely visited by a number of geckos who seem to enjoy being hand-fed bits of papaya or scrambled eggs.  As a  side note, we have observed that they treat these two foods quite differently.  They gently slick papaya and eat small bits.  Pieces of egg, though are snatched and chomped in a manner similar to when they are hunting live insects.  (By the way, geckos have no teeth and couldn't hurt you if they tried.)  They seldom show up for lunch or dinner, and although we're not sure why this is so, it is perhaps a good thing because our human dinner guests might not share our tolerance for lizards on the table.

Here are a few other things we've learned by careful observation over the years:
  • They are very territorial.  The same geckos are always in the same areas,  and they will defend their territory against other geckos.  Sizes of territories vary from a six-foot section on an outside balcony to a wall in a room.
  • They pair off.  A male may have one to three exclusive consorts who take up residence in the same territory.  "Hook" and "Mona" have been a pair on our lanai for around two years, for example.
  • They can live a long time.  I read somewhere that in captivity geckos can live 12 years or more.  Our oldest was at least 5 or 6 years old when he disappeared one day.  He was a resident on our lanai when we moved in and was already mature.  He lived in the same territory and visited the outdoor breakfast table nearly every day for 5 years.  We named him King Gecko because he was the largest we had seen, and he still holds that record.
  • They have distinct personalities.  If you are someone who puts geckos in the same category as cockroaches or rats, you may find this difficult to swallow.  But we swear there are consistent individual differences among our favorite geckos.  Some are calm and mellow, others are divas.  Some like to "hang out" with humans even if they aren't being fed, others are more materialistic.  Some are bold and take risks, others are timid and wimpy.  I admit I'm violating my scientific training with this blatant display of  anthropomorphizing, but I think mine is more defensible than, say, Disney's Lion King.
  • No suction cups or sticky feet. Contrary to popular belief, the gecko's ability to climb vertical surfaces and even walk upside down isn't because their feet are sticky or their toes have suction cups.  The truth is much more amazing:  their toes are covered with thousands of tiny hairs that adhere to even the smoothest surface because of something called van der Waals forces.  They adjust the amount of adhesion by bending their toes backwards (i.e. up) away from the surface for less or putting them directly on the surface for more.  When we see them walking flat on our table their toes are curled upward, which is kind of cute.  A more thorough explanation is in a recent Scientific American article here.
  • Being a baby gecko is dangerous.  In their native Madagascar, baby geckos are totally on their own and face numerous predators as soon as they emerge from the egg.  Here in Hawaii they have only a few enemies:  birds, cats, mongoose, humans, and....adult geckos who will eat them if they can catch them.
  • Geckos poop in the same spot and do it dangling.  Geckos are like cats in that they prefer to poop in the same location.  Unlike cats, though, they don't cover it up afterward because they let it drop while dangling from an overhang of some kind.  By the way, the poop reminds me of parakeet droppings.  More than you really wanted to know?  Read on.
So far I've mentioned only our interactions with geckos outside in our garden or on our lanai.  But living in Hawaii means living with at least a few geckos inside your house.  Unless you keep your house hermetically sealed they can easily infiltrate any screen door or window that you leave open.  We leave our doors and windows open all year, all day and night,  nearly every day because the weather is so pleasant.  In fact, our house has no central heating or air conditioning so closing it up doesn't really make much sense.

Having geckos live in your house is good in that flying insects like mosquitoes are a main part of their diet.  However, what goes in comes out, and cleaning up gecko poop can get old real quick (see my related blog, "Cleaning Up Poop In Paradise"). The dilemma is how to maintain this at a "reasonable" level.  Many people adopt the "search and destroy" approach, killing any gecko they can with a fly swatter or a shot of insecticide.  Others adopt a "let it fly" approach,  which means they save money on mosquito repellent but spend a fortune on cleaning supplies.

Our approach involves a "catch and release" program, and has resulted in us becoming very expert at catching geckos and relocating them outside.  Catching a gecko isn't easy because they are very fast and can be quite adept at finding nooks and crannies where you can't get at them without destroying your furnishings.  However, we have learned how to turn their traits to our advantage and with a little teamwork, we are very successful.  The trick is to use the gecko's behavior against it.  For instance, they are fast but they don't have much stamina.  Armed with a couple of furniture dusters, we can often run a gecko back and forth until it tires enough to allow one of us to gently pick it up and hold securely in our hand.  By the way, we know when they are ready for pickup because they turn dark.  This process can be hastened if we can get them onto carpet, because it is difficult for them to run and they quickly tire out.

Over the years we've learned their likely defensive strategies and we can even use these against them.  For example, one strategy is to run toward the largest vertical surface -- which might be one of us.  Another is to hide underneath the nearest object -- which might be one of our feet.  Often they will take refuge inside one of the dusters, which of course plays right into our hands.

We relocate our house geckos far down the street in some suitable bushy habitat.  We learned early on that we had to take them quite some distance away or else they would return (perhaps their territorial attachment kicking in).  This means that our approach to gecko control is not only humane, it also has the benefit of providing us with exercise.  It also benefits our neighbors by entertaining them with our frequent relocation trips!

Well, there is still more gecko knowledge and wisdom I could impart, but I'm sure that by now you've learned much, much more than you ever wanted to know about geckos. As for me, I'm thinking of starting a twitter feed for geckos, or maybe a Facebook page for our favorite geckos, more maybe apply for a grant to study the potential uses of gecko poop............... I'll keep you posted.

18 comments:

Anonymous said...

I live on Oahu in Temple Valley and have three that hang around. I put out honey in soyu dishes and they love me! I add gecko supps to honey to help with color and reproduction. I think the huge one with a scar is the male, and the two others are his "women". One of the ladies, Niho, I have had for 5 years and she used to live in a terrarium, before I turned her loose at this new house. My name is Lydia and I am overjoyed to find another person obsessed with Phelsuma L. Laticauda as much as I am.

Jen P said...

So my question is: What color is gecko poop, because I'd like to paint the walls that color! Then I can have the best of both worlds - geckos in the house to eat little critters, and not have the walls stained (I'll still clean them, but less nasty looking in the meantime, ya?)

From what I've seen, it's just brown. May go for some nice taupe type color. :~D

Signed, another gecko-love

Richard Sherman said...

Jen --good thinking! We recently replaced the carpeting in parts of our house and tried to get a pattern that was "pre-pooped," with some dark and light specks and swirls that would hide the gecko spots.

The color may depend on what they eat. Ours seems to be mostly a light to dark brown, so taupe might work!

RS

Anonymous said...

One of the wild geckos in our place poops right over our bed. I keep finding little droppings with white little dots on our bed, guess where? ON MY PILLOW! Is there a way I can peacefully convince the gecko to drop elsewhere?

Richard Sherman said...

Since geckos tend to always go in the same place, you're faced with only two possibilities. Put a canopy over your bed or catch the little sucker and relocate him. The poop-on-a-pillow is definitely one thing that would lead us to take this one way, way, down the street......

Good luck.

FivesFan said...

Richard - Loved you blog about the Geckos. We live down the road from you in Ocean View and you have encouraged us to learn more about our friends. The thing is though that ours are brown, so we can't really tell them apart, aside from the individuals size... Thanks for a great read and for more than I ever wanted to know about Geckos...

suzannah pennington said...

While I was at work two adorable baby geckos kept getting in the way...so I decided to capture them and bring them home, but I don't know what to feed them, they are smaller than my thumb!!! I do know they eat cockroaches when they get bigger and we have a cockroach problem at home

Deb Kline - FivesFan said...

Suzannah - I know they eat small bugs and such, bet at the restaurant we go to, they are also seen eating the guava jelly.... Google and see what you come up with... Where are you at?? FivesFan

Richard Sherman said...

Suzannah & FivesFan --

The Gecko Whisperer here. I've found that Geckos have local food preferences -- things that other people's geckos love ours find blah. They are omnivores, and so tropical fruits like guava, mango, papaya, etc. are likely attractive to them. Ours are fond of papaya or mango mash -- I take the edge of a spoon and scrape some goop and place it on a "gecko feeding station" (aka yogurt container lid) in a couple of spots (to allow more geckos to feed at the same time). However, being "meat" eaters they also crave protein. They naturally get this protein from catching flying insects like mosquitoes, gnats, moths, and cockroaches(sadly, they aren't interested in ants). Note, they don't have teeth so if the insect is larger than they can swallow they shake it like a crocodile until a bite-sized piece comes off.

Our geckos are particularly fond of bits of scrambled eggs. I makes sure the pieces are very small because if they try to eat a larger hunk they will use the shake-it method and you'll have scrambled egg all over the place. We've tried bits of bacon, steak, ham, chicken, etc, and they don't seem all that interested.

I'd stay away from sweet stuff -- it just seems unhealthy to me.

Oh -- and keep in mind that they are also cannibals and will eat small geckos, so I hope your new babies don't wind up as meals for larger ones.

Good luck!

RS

armiejiel doroy said...

Richard we live in Philippines and live peacefully with the geckos here but....we keep finding what looks like gecko poop on the walls, ceilings etc (not on the floor). From time to time we hoover up but recently my son pointed out that the poop was moving. Sure enough at the end of the poop was a little worm moving backwards and forwards and slowly moving it along. Naturally this has caused some concern as to exactly what it is, and even if it is actually gecko poop, but what else could it be? Have you any experience of this happening? Regards Armiejiel

Richard Sherman said...

Armiejiel --

Wow, this sounds bad! I doubt very much that this is gecko poop but most likely is some kind of nasty critter. Is the "poop" part maybe really a part of the worm thing and not really poop? It seems odd that the worm would drag a piece of poop around with it.

Our geckos have never had any parasites that I know of and I certainly have never seen anything like this. I suggest you consult somebody is an expert and please post what you find out.......

RS

Unknown said...

Great blog. Very knowledgeable. We have two spotted leopards and my kids wanted to know why they went in the same spot. They named them Cosmo and Wanda from Fairly Odd Parents.

Richardona said...

Armiejiel, sounds like a "Household Casebearer" moth (Phereoeca uterella), at least its larval form. Pretty harmless insect.

js said...

Aloha! An ideas on how to aid some found eggs in successful hatching? We are staying at a friend's gecko- friendly cabin on Kauai and found two eggs inside. It's a VERY indoor outdoor home. Do we leave them inside? Move them out? Place them in a jar with food till they hatch? Mahalo!

Richard Sherman said...

js- Believe me, they don't need any assistance. But if you move the eggs outside, find a crevice or a hole so that they won't be found by predators (including other geckos). The little ones will fend for themselves right from the start as far as finding food (flying insects mostly) and they're main concern is avoiding big geckos and other predators to get big quickly.

Anonymous said...

A Crested Gecko does not (unfortunately) poop in the same spot.

Richard Sherman said...

Good to know. I'm not familiar with the Crested Gecko -- they aren't one of the types that were introduced to Hawai'i. I admit I'm not sure about the poop patterns of the varieties other than the Gold Dust Day Gecko because they are active at night and aren't nearly as sociable.

RS

Matt Brandt said...

Any idea how to keep them from eating the papaya in your garden? Do the ever damage the fruit themselves, or just go for already damaged fruit?