Journal archives for January 2019

January 04, 2019

A Merlin Fly-by: Observation of the Week, 1/4/19

iNat user @nanorca13 took this amazing photo of a merlin harassing a bald eagle in Canada and it’s our Observation of the Week!

Sorry for the holiday-induced delay, folks, but Observation of the Week is back for 2019!

Although he’s always been interested in nature, “from spending summers on the farm in southern Saskatchewan when I was a kid with the pronghorn and coyotes to trips to the beach here on Vancouver Island,” Warren Cronan says “I literally got into my obsession about six years ago when I injured myself running trails up the mountain. So because I couldn't run I grabbed my little camera and started hiking and taking pictures.”

As his interest in photography grew, Warren upgraded his gear and began posting his photos to iNaturalist in 2015.

Birding has become my main focus of interest and the merlin observation and pictures with the eagle happened while I was looking off the back deck of my parents’ house. This was not the first time I've seen a merlin chasing an eagle here in the middle of Nanaimo...I believe the eagle got too close to the the trees where the merlins had a nest and were spending the summer. I kept taking pictures of the eagle until the merlins finally chased him off...I got some great pictures of the eagle and a few with a merlin in the pic with him. I'm glad others have enjoyed it.

A type of falcon, the merlin is a small - wingspan about 50–73 cm (20–29 in) - but quick and aggressive bird that often hunts other birds on the wing and is known for fiercely defending its territory from other raptors. Pete Dunne, in his Hawks in Flight (with David Sibley and Clay Sutton), writes “An observer may use this aggressive tendency for identification purposes and as a means of detection. High-flying merlins often betray themselves and distinguish themselves because they are vigorously harassing another raptor (even ones as large as the Golden Eagle).” Merlins are found throughout both Eurasia and North America.

“I almost always have my camera handy and ready no matter where I am,” says Warren (above, with said camera), “and my ability to track birds in flight has improved considerably over the last few years.” He uses iNaturalist as a place to organize and share his observations, as well as get ID help from other users, but says “as much as I get out of posting my observations and following others, it is being out in nature observing that I live for, and capturing an interesting shot is just icing on the cake.”

- by Tony Iwane. Some quotes were lightly edited for clarity.

- Here’s some great footage of a merlin hunting and feeding its chicks.

- And this osprey nest cam video of an attacking bald eagle shows you exactly why birds don’t want bald eagles around their young. This video may be difficult to watch for some.

- Falcons and eagles may look and behave similarly, but they are only distantly related if you delve into their genes. Falcons are in fact much more closely related to parrots.

Posted on January 04, 2019 10:50 PM by tiwane tiwane | 7 comments | Leave a comment

January 14, 2019

A Mouth Gaping Viper - Observation of the Week, 1/13/19

This “yawning” bamboo viper, seen in India by @prasannaparab, is our Observation of the Week!

“When I was in high school I used to collect nature and wildlife related newspaper cuttings, and also got hold of a few old National Geographic magazines, which helped in developing my interest on this subject,” says Prasanna Parab. “At that time, going into the wild or nature watching was just an unknown domain at home.”

He says that mentors like Paresh Porob (Range Forest Officer, Goa (India)) and Shambhu M V (Indian Forest Service) “sensitized me about nature, provided me the opportunity and inculcated the essential discipline and patience required for documenting natural history, this presented a plethora of opportunities for me to travel in the wild.” Prasanna began photographing butterflies - his photo of which have been used for the management plan of the Netravali Wildlife Sanctuary, where he has been named an Honorary Wildlife Warden - but is now also taking photos of birds, arachnids, orchids, and more.

Prasanna encountered the above snake back in 2014 while visiting Netravali Wildlife Sanctuary with Honorable Wildlife Warden Benhail Antao and Louise Remedios E Antao and tells me

we sighted this bamboo viper perched on a stick near a stream in an evergreen forest. Since none of us had a macro lens, we patiently watched this for 5-10 minutes, flickering its tongue with very slow movement. Suddenly, I saw it slowly opening its mouth, I was far away owing to the fact that I had a Canon 100-400mm tele lens; I quickly managed to snap 6 sequential images of this yawning behavior.

While the viper might appear to be baring its fangs in preparation to bite or at least scare off a threat, that’s likely not the case. I consulted with NHMLA herpetologist Dr. Greg Pauly (@gregpauly) and he was sent me an explanatory list of four probable reasons a snake might mouth gape (aka yawn):

1) Stretching fangs and jaws after eating a large meal. This is basically just getting everything back into a comfortable position. Owners of pet snakes will be quite familiar with this. Sometimes people think this is because they need to reposition their jaws after "unhinging" them, but of course snakes don't unhinge their jaws. That's just a common misconception.

2) Stretching fangs and jaw musculature in preparation for eating a large meal.

3) Drawing in chemicals that can contact the vomeronasal organ.

4) In some species, a wide open mouth is used as a threat/warning display. This is common in cottonmouths and parrot snakes.

5) There are certainly other reasons still awaiting to be discovered. Owners of pet snakes will have witnessed their snakes yawn in situations that don't fit into the above categories. For example, I think snakes sometimes yawn just to stretch critically important muscles and joints that don't get much day-to-day use otherwise. But nobody has really demonstrated this.   

Dr. Pauly believes this bamboo viper is likely opening its mouth for reason number 3 or possibly 5, and is not aware of this species using it as a threat display.

This species of viper is found in southern India, often among bamboo, and is known to prey on birds, lizards, and other small animals. It should not be confused with other members of its genus, some of which are also commonly called bamboo vipers. Like all vipers this species has front fangs (shown wonderfully in Prasanna’s photo) which can fold back when not in use, and its venom is primarily hemotoxic, meaning it damages and disrupts the circulatory system. Members of the other major venomous snake family, Elapidae (cobras, mambas, most sea snakes, among others), have fixed front fangs and their venom is generally neurotoxic, meaning it disrupts the nervous system.

While he has been photographing wildlife for many years, Prasanna (above) tells me me he only recently discovered iNaturalist while at “the Spider India Meet 2018 at Amba Ghat (Maharashtra, India) organized by Siddharth Kulkarni (The George Washington University, Washington DC) and Dr. Atul Vartak.” He attended a talk by Rohit George (@rohitmg) that covered citizen science and soon started looking into iNat. He says, “I went through the website several times and noticed that a lot of knowledge is being shared and circulated which can aid science in a huge way, thus prompting me to make more keen observations and share them on iNaturalist.” He’s currently posting both his past observations (like this one) and present observations here.

- by Tony Iwane

- Nice article about Siddharth Kulkarni and Dr. Atul Vartak’s documenting of a new spider species in India. 

- Here’s a New York Times column featuring Rohit George and an amazing spider-mimicking moth he found.

Posted on January 14, 2019 05:23 AM by tiwane tiwane | 4 comments | Leave a comment