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More Waugh Bridge Bat Colony

My husband and I visited the bats once again last Friday night. We arrived a bit late - the "vortex" was there, but I think the majority of bats had already emerged, so it wasn't quite as spectacular as the time we went a couple of months ago (didn't post anything on that).
During that time, we did observe an incredible vortex of bats and a tremendous, steady stream of them as they emerged from the vortex. It really was an amazing sight to behold!
Here are some shots of the surrounding scenery, the dandelion fountain, and the bridge...






"The Waugh Bridge Bat Colony" (hlb 5-2-10) "Waugh Bridge Bat Colony Pontoon Boat Tour" (hlb 6-15-09) Buffalo Bayou's Waugh Bridge Bat Colony The Waugh Bat Monitor

White-Nose Syndrome Spreading Rapidly

WNS fungus on the nose of a little brown bat photo courtesy of Ryan von Linden, NY Dept of Environmental Conservation
Since my first post on White-Nose Syndrome, three more species and several more US states have been affected. First detected in February 2006 in New York state, the then-unidentified disease spread to Vermont, Massachusetts, and Connecticut by Spring 2008. In Spring 2009, it spread to New Hampshire, New Jersey, and Pennsylvania and then south into Virginia and West Virginia. (There was even one case confirmed in France in December 2009 - a bat tested positive for the WNS fungus but showed no symptoms.) In February/March 2010, it spread out into Tennessee, Maryland, and Ontario, and in April/May 2010, the fungus was confirmed on bats in Delaware, Missouri, Oklahoma, and Qu├ębec. This brings the total to 14 US states and 2 Canadian provinces.
The rate that it is spreading is quite alarming - it was thought that once it hit the more southern latitudes or more northern latitud…

The Sucker-Footed Bat (Myzopoda aurita)

Myzopoda aurita ready to cling! - photo by Daniel Riskin
This is the sucker-footed bat, or Myzopoda aurita - myzo meaning "suck," poda meaning "foot." Though contrary to its name and what was previously thought, it does not adhere to surfaces by means of suction but rather by wet adhesion, as research by Daniel Riskin and Paul Racey has discovered.
These little guys (and girls) are two inches long and weigh 1/3 of an ounce. They roost head-up, way up in the furled leaves (that open at the top) of the Traveler's tree in Madagascar. Only six species (out of 1,200) of bats are known to roost in an upright position. They do so because it allows for a quick escape from predators.
Traveler's tree - photo by Daniel Riskin
These Old World bats have flat to slightly convex pads at their wrists and ankles that enable them to cling to the smooth surfaces of the leaves. Or Plexiglas.

Myzopoda aurita climbing on Plexiglas - photo by Daniel Riskin
foot pad of Myzopoda aurita …

Bats & Their Bat Flowers

help...stuck... (Anoura caudifer) - photo by Nathan Muchhala
No, this nectar-feeding bat is not really stuck. (Nor what I would call a dainty eater.) Bats are known to push their heads into bat-flowers to lap up the nectar.
Anoura caudifer - photo by Nathan Muchhala
Anoura fistulata - photo by Nathan Muchhala
Indeed.
(I love these photos! They're so funny to me!) A bat will insert its head into the flower - even when its tongue is longer than the flower's tube. It extends its tongue as much as it needs to, then retracts it, lapping the nectar much like a dog drinks water. By pushing its head into the flower, the bat collects lots of pollen on its head and chest, inadvertently transferring it to the next flower.
Moths are also nectar-feeders; however, when a moth drinks nectar, its tongue acts as a straw. So if a moth evolves a tongue longer than the floral tube, it could potentially partake of the flower's nectar without actually pollinating it. Therefore, the flower is always ev…

Chiropterophily: Bat Pollination

I see you! Geoffroy's tailless bat (Anoura Geoffroyi) - photo by Nathan Muchhala
Ever since coming across this word, I can't stop saying it: chiropterophily. Chiropterophily, or pollination of plants by bats, is very common in the tropics. Hundreds of tropical plant species are exclusively or at least partly pollinated by nectar-feeding bats.

Many tropical flowers are night-blooming, specializing in attracting bats. Bat-flowers are typically white, cream, or pale green in color, making them easier to see in the dark. They usually have a musky, fermented odor - like that of the bat - or sometimes a fruity odor. They have a large, sturdy, open shape with long, bushy anthers so that the bat's head and chest get coated in pollen when it visits. In return for the bat pollinating the flower, the flower provides the nectar that these high-energy flying mammals need.*

Tube-lipped nectar bat (Anoura fistulata) - photo by Nathan Muchhala
Nectivorous bats have both good eyesight and a kee…

Animal Pollination in the Tropics: Hummingbirds to Hawkmoths

Inside a tropical rainforest, there's not a lot of wind, apart from high up in the canopy, and plant species tend to be very rare and quite far away from each other. Therefore wind pollination is not an effective means of plant reproduction. The preferred method is animal pollination, and many fascinating processes have evolved both in the pollinizer (the plant) and pollinator (the animal).

It's a coevolutionary process - both plants and pollinators become specialized to attract each other. Tropical plants have evolved flowers that entice their preferred pollinator - be it hummingbird, insect, or bat - so that the pollinator will hopefully carry the plant's genes, via the pollen, to another plant of the same species. Sometimes it entices by rewards like nectar - making it a mutualistic relationship - sometimes by trickery,* but it will match its characteristics to the characteristics of a specific pollinator and discourage all other pollinators. At the same time, the pollin…

The Disk-Winged Bats of Lapa Rios

Spix's Disk-Winged Bats (Thyroptera tricolor) roost upright in rolled Heliconia and banana leaves.


You can see the little suction discs on the thumbs and ankles. These lightweight little insectivores use these to cling to the leaves.




The other bat species found at Lapa Rios are the Greater Fishing Bat (Noctilio leporinus), Thomas' Fruit Eating Bat (Artibeus watsoni), and the Greater White-Lined Bat (Saccopteryx bilineata), which is seen but uncommon.

These pictures were taken on 6/29/08 along the Osa Trail at Lapa Rios. Link to "Costa Rica: Day 11 - Lapa Rios Osa Trail."


Read about the Sucker-Footed Bat (Myzopoda aurita) that also roosts head up in "Sucker-Footed Bats Don't Use Suction After All" (Science Daily).

Eyeshine in Nocturnal Animals

Peters' Epauletted Fruit Bat (Epomophorus crypturus), Kruger National Park - photo by Peet van Schalkwyk

Have you ever noticed how under certain lighting conditions some animal's eyes seem to glow? Animals that are nocturnal hunters - and a few of them that are not - have something called eyeshine. Eyeshine is the light that we see reflected back from the animal's tapetum lucidum (a membrane behind the animal's retina). Light enters the eye, passes through the retina, strikes the reflective membrane, and is reflected back through the eye toward the light source. This phenomenon makes the most of what little light there is at night for these nocturnal creatures.

a moth with pink eyeshine
Humans can display the red-eye effect in flash photography, but we do not have a tapetum lucidum, and thus, do not have eyeshine.

Eyeshine is best observed by wearing a head lamp or holding a flashlight at eye level against your temple because the light is reflected right back into your li…

Be Kind to the Googlebots!

As I posted last week, I am currently working on optimizing this blog. In doing so, I came across something that I am now completely fascinated with (and mostly because of its name and how I imagine it to look in my head): the Googlebot.

(I think I imagine it to be something like the little obsessive-compulsive robot M-O that cleans things in WALL-E.)

So there's not actually a Googlebot - it's Google's search bot - or spider - software that searches the web and indexes the information it finds in the Google search engine. Here are some of the things the Googlebot likes:
Relevant and descriptive titles (blog title bar, blog post titles, titles in the permalinks)*Relevant and descriptive labels (categories, tags) Relevant and descriptive anchor textYou updating your blog often!Anyway, these are some of the things I'm implementing in an effort to be kind to the Googlebots, so, again, please bear with me while I'm changing some things around (like titles, labels, and perm…

Bat Anatomy and Behavior

Bats are the only true flying mammals. They belong to the order Chiroptera (coming from the Greek words for "hand" and "wing"). They are further divided into 2 suborders: Megachiroptera (megabats) and Microchiroptera (microbats).

Bats account for 20% of all of the world's mammals. They are present on every continent except Antarctica. They are integral in seed dispersal and the pollination of certain flowers, and they help keep the insect/pest populations down.

Being a mammal, the skeletal structure of a bat's wing is more like a human arm than a bird's wing. In fact, a bat's wing very closely resembles a human arm - the difference is in the proportions. (Imagine your arm with extremely elongated fingers - link to bat wing anatomy).

Monteverde Bat Jungle
Also, the difference between bat and bird flight is that bats do not flap their entire forelimbs like birds, but rather flap only their spread-out "fingers".

bat skeleton, Monteverde Bat Jungle

Shuffling and Optimization

Please note that I will be shuffling some things around because I am currently doing some site optimization. This will involve reworking some of the posts already up and hopefully adding more posts regularly, especially those bat- and Costa Rica-related. (My husband and I visited Costa Rica a second time over the holidays!)

One reader commented about the blog's colors and fonts, saying it was kinda hard to read. I don't have a problem with it (but different monitors display things so differently) and no one else has commented on this; but if it is a problem, I don't want to turn people away with my color and font selections. So let me know.