Photo by Sarah Hadley 

Species of the day – March 4, 2013 – Purple-crowned Fairy (Heliothryx barroti)

The purple-crowned fairy was a new capture for us. We caught one a few years ago, but nothing since. Today we caught two! These are very pretty hummingbirds. They are also noteworthy because they have quite a short, but very pointy bill. This is an ideal bill for stabbing through flowers to steal the nectar. Species that steal nectar without providing pollination services to the plant are called ‘nectar robbers’. There are species of hummingbirds and also bees that we typically think of as pollinators who commonly employ this “robbing” strategy. Consequently many of the flowers have evolved tough protective layers to try and impede these robbers.

Photo by Sarah Hadley

Species of the day –March 3, 2013– Rufous-tailed Hummingbird (Amazilia tzacatl)

Photo by Sarah Hadley

Just because a species is common, or we see it all the time, doesn’t mean it isn’t interesting. I thought that it was about time we mention this common species of hummingbird. Rufous-tailed hummingbirds are a mid-sized. They are similar in weight to the green-hermits (a bit lighter), but they have a much shorter bill and behave very differently ecologically. Rufous-tails are territorial hummingbirds meaning that they defend flower resources and drive off other hummingbirds that try to visit them. We hear these guys chattering all over the place. They seem to do very well in disturbed areas and are probably one of the most common visitors to people’s gardens here in Costa Rica.

I was out last night just before bed covering some heliconia flowers with mesh bags. I cover the flowers with these bags to prevent the hummingbirds from being able to access them. That way I can run experiments both with and without hummingbirds present depending on the experimental questions. I was covering them after dark since I wanted to leave the old flowers open to hummingbirds throughout the whole day and then have the new flowers covered before they opened the next morning.

The same clump of heliconia has a whole other suite of visitors at night. In the day there are mainly hummingbirds coming to drink the nectar. At night it seems to be when the insects come out. There are many species of Orthoptera (grasshoppers, crickets, katydids) that come to eat the flowers that were open during the day. They often eat any remaining pollen off the anthers and then the other soft parts of the flowers. I have a bit of a love/hate relationship with these critters since they are really cool and I usually see new exciting ones each time, but they often eat my carefully treated samples rendering them useless!! I also saw a giant round beetle that was bright green (I couldn’t ID it unfortunately) and a neat frog. There were ants with very large and imposing mandibles patrolling the leaves in the area where I had set my bag down. I had to be careful not to irritate any of the fearsome ants since I know from experience that their bites can be surprisingly painful!

As I worked I could hear both a Mottled Owl (Ciccaba virgata) and a Black-and-white Owl (Strix nigrolineata). There are also a great many other noises that I can only imagine what they may have been. I noticed that the large hairy spider from a few weeks ago was still hunting in the spikes of a palm tree near one of the plants. On my way back a kinkajou crossed through the bamboo and I was able to get a great look at him with my headlamp. Back at the cabin a little anole lizard had slipped in and I spent about ten minutes chasing him around before finally cornering him in the shower and letting him out. All in all it was a good reminder that not everything sleeps at night and much of the activity takes place after dark.

Photos by Sarah Hadley

Photo by Sarah Hadley

Species of the day –March 2, 2013– Stripe-throated hermit (Phaethornis striigularis)

This little hummingbird often seems like a tiny version of the green hermit. It is a bit less than half the weight (2.5 grams or about the same as a penny). It is also brown rather than green. Like its larger cousin the green hermit, the stripe-throated hermit is a trapliner and does not defend flower resources. They are actually quite good at sneaking in undetected and stealing nectar right under the bills of territorial hummingbirds such as Rufous-tailed Hummingbird (Amazilia tzacatl). Mauricio and Esteban often refer to these little guys as “mosque” which means “fly”. They are fun birds to work with since they are quite tame and will come and visit the readers even as you are working with them.

This grainy photo is not actually of the hummingbird equivalent of a Sasquatch, but shows a stripe-throated visiting one of the readers. Interestingly, these tiny little guys seem to be moving further than we might have thought!

Photo by April Bartelt

Photo by Sarah Hadley

Species of the day – 1 March 2013– Rhinoceros beetle (Dynastinae)

This beetle looks a bit more like a small triceratops! Mauricio tried to bring it back to show his daughter, but it ripped out of the plastic bag he had put it in and then pulled open the zipper on his backpack. Clearly they are quite strong. Supposedly they can support up to 100 times their own weight. There are over 300 species of rhinoceros beetles.

Photo by Sarah Hadley

Species of the day –February 28, 2013 – Leafcutter ants

Leafcutter ants are amazing. The amount of work the preform is really impressive. According to Wikipedia “Next to humans, leafcutter ants form the largest and most complex animal societies on Earth.” and “…containing eight million individuals.” We have found many of their giant mounds of excavated dirt and long cleared trails over which they haul leaf cuttings. The leaves they cut are used to feed fungus that they cultivate underground. These photos show a line of workers coming down a tree and also a place where they have had to drop a bunch of leaves in the hot sun.

Photo by Sarah Hadley

Photo by Sarah Hadley

Species of the day –Back-dated#4 – Orange-collared Manakin (Manacus aurantiacus)

While this is a very bright and exciting bird just because of the way it looks, it is also exciting for another reason. The males display in a group at a location called a ‘lek’. Part of their display involves flying back and forth making a sound that sounds like a string of firecrackers going off.

Photo by Sarah Hadley

Species of the day –Back-dated#3 – Golden silk orb-weaver (Nephila clavipes)

This giant spider is often as big or bigger than a large person’s hand! It is called a golden orb-weaver because its web is like strands of gold. The web is also very strong and can catch quite large things – even hummingbirds!

Species of the day –Back-dated#2 – White-tipped Sicklebill (Eutoxeres aquila)

Here is an amazing example of an adaptation (extreme bill curvature) that allows this species of hummingbird to access flowers that have curved corollas preventing hummingbirds with shorter or less-curved bills. These hummingbirds have a small indent in their forehead that seems to be a place where a lot of pollen can collect. Clearly this is a very neat example of co-evolution.