Soundbites is a weekly (biweekly, occasionally) feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound. Welcome to November, everyone! Fall is definitely here! I promise I’ll have a proper ASA post up soon, but in the meantime here are your Soundbites for the week!

Cruise ships may be having an impact in developing tourist marketsthe good thing about ecotourism is that you’re not openly depleting resources the way you used to be. The bad thing about ecotourism is that increased exposure can degrade the environment. Places like the Eastern Mediterranean and the Adriatic are facing increased noise levels because of increasing tourism.

Microclimate affects frog callsabiotic noise like streams and waterfalls can have as much of an impact on vocalizing animals as anthropogenic noise. Here the researchers wanted to know if frogs in different microclimates (near stream, far from stream) were changing their call frequency to overcome stream noise, and they were!

Fun link of the week this week comes from Holger and Radiolab–the story of a vest that helps deaf people hear.

 

Soundbites is a weekly (biweekly, occasionally) feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound. I’ve been doing really well on this weekly thing, but I might break my streak next week as I’ll be in Indianapolis for ASA(!). That just means you’ll get a real blog post from me next week!

Aposematism led to increased vocal diversity in poison frogstip o’ the finder hat to my Garcia labmate Lindsey for this one, and it’s brilliant. You know those little brightly colored poisonous frogs? These authors wanted to know if aposematism (displaying bright colors like that as a warning to predators) might lead to increased vocal diversity, since they’d have to worry less about predation. And it did! In conjunction with sexual selection, aposematism allowed the evolution of a broader vocal repertoire!

Silvereyes shift their frequency down in urban noise–and it worksThese are silvereyes. Silvereye birdsThey’re really cute. You can find them in Australia and New Zealand (which is where I took this photo). Most animals shift their frequencies up above urban noise, but it turns out silvereyes shift theirs down. This increased the predicted effective space of their alarm call 20%!

Fun link of the week: Robert Krulwich of Radiolab wonders about singing bats!

 

Soundbites is a weekly (biweekly, occasionally) feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound. 

High-frequency vessel noise may have an effect on marine mammals in shallow watermuch of the anthropogenic noise that we’re concerned with at ORCAA, whether it’s road or vessel noise, is low-frequency because of the attenuation of higher frequencies. However, in shallow water, the high frequencies may not attenuate as much and may therefore cause masking for higher-pitched odontocetes.

Direct-developing frogs are more reliant on climate cues to start callingwhat a week, we get one whale link and one frog link! There are some species of entirely terrestrial frogs that don’t go through a tadpole stage; instead, they hatch as mini adults. However, the eggs still need to be kept moist while they’re developing. These researchers found that the onset of calling was more closely tied to high humidity and rainfall than it was to overall air temperature, which is a different cue than most species of tadpole-metamorphosing frogs.

Fun link of the weekI’ve been practicing for my presentation at ASA in a couple of weeks, so I’ve been asking myself this question regularly: “does my voice really sound like that?” Here Greg Foot examines why our voices sound different on recordings.

Soundbites is a weekly (biweekly, occasionally) feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound. Well, Soundbiters (your new collective noun), term has officially started and the ORCAA students are off and running. 

Automated frog call detection–it WORKS! Oh man guys, this is so cool. These researchers developed an automated system for frog identification by call, and it worked even on species they didn’t train the detector on! Talk about huge implications for more efficient monitoring in remote areas!

Cichlids aren’t impacted by boat noise playback: we talk a lot at ORCAA about the negative impacts of anthropogenic noise, so occasionally it’s refreshing to see a species that isn’t impacted in our ever noisier world. Development of this species of cichlid fish was not impacted by playback of boat noise.

Fun link of the week: to be totally honest this has very little to do with sound except that an explosion is involved (just a small explosion, I promise). It’s the first day of October and that means PUMPKINS!! You can make a self-carving pumpkin with calcium carbide and hydrogen peroxide! I would totally try this this Halloween except I’m spending the week prior in Indianapolis for ASA.

 

Soundbites is a weekly (biweekly, occasionally) feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound. Can you believe it’s September already? I can’t! This is a frog-heavy post because a lot of interesting frog stuff has been coming out lately; my apologies to marine mammal fans.

Multimodality as a frog coping mechanism for traffic noisewhat’s multimodality, you ask? Multimodality refers to communicating in more than one sensory mode; in this case, using both vocalizations and visual cues to communicate with potential mates. While these authors found that switching sensory modalities wasn’t the case for European tree frogs, they do say that this may happen in other species (like the tungara frog I mentioned in my post about the Frog Communication Symposium).

Traffic noise causes stress in frogsthis is VERY cool. Traffic noise playback causes physiological signs of stress in the form of increased corticosteroids in female wood frogs, who use the chorus of male frogs to orient toward the breeding pond. Not only is there stress, but they tend to freeze up and not move, which may impede breeding migration. This may be because the stress hormone is causing an immobility response, or because they can’t figure out where the chorus is due to masking.

Fun link of the weekyou know how usually I post a pop press article or a video here? Well this week, it’s a third paper. It’s a paper on coffee roasting acoustics. Apparently it might be helpful for coffee roasters to listen to their beans cracking. I don’t drink coffee, but many of the ORCAA do (Holger especially!), so this seems like a great way of combining two of the lab’s loves!

Soundbites is a (hopefully) weekly feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound. Because I’ve been traveling, it’s taken a short hiatus, but that only means I’ve got even more awesome research to share!

Spring peepers change their calls in response to noiseI’ll get this one out of the way first because it’s relevant to my research. A congeneric of my study species is showing vocal plasticity! This is awesome! However, the lab that did this didn’t use anthropogenic noise, but focused on chorus frequency bands. Still, exciting stuff in the world of frog communication!

Anthropogenic noise affects development of embryonic sea haressea hares are marine invertebrates kind of like sea cucumbers. This study shows that with playback of anthropogenic noise, they develop less successfully and mortality is increased. It just goes to show that even non-acoustic species are affected by noisy situations.

Icebergs are NOISY, manhere at ORCAA we talk a lot about the biotic and anthropogenic additions to the soundscape, but we can’t neglect the abiotic additions from things like icebergs. Also, this has to do with Antarctica and Michelle is going there in a few months, so I had to post it! The breakup of substantial icebergs is enough to increase ocean noise levels in mid-to-equatorial regions (really far away) for a year and a half. Dang.

Anthropogenic noise causes different anti-predator responses in two sympatric fishI wasn’t going to post this one, but then I saw that they were testing the response to a visual cue and that was what had changed and it got me thinking. It seems that the fish that changed its response (the stickleback) is made considerably more vigilant by the presence of noise and therefore responds more quickly, while the minnow doesn’t respond at all. Since the fish are preyed upon by the same predators, this has some interesting community-wide implications. Very cool stuff.

Fun Link of the Weekhey everyone, it’s Shark Week! But unfortunately certain channels seem to have forsaken scientific information on sharks in favor of increasing their ratings. So here’s a reputable source of shark information talking about sharks making sounds (spoiler alert: they don’t, really)! If you want more awesome shark science that is grounded in fact, take a look at this YouTube playlist here.

I’ll be back in Corvallis next week, and Soundbites will resume its sort-of-normal schedule!

I didn’t post a Soundbites this week because I was very busy on Wednesday doing something very important, so I thought I’d talk about that instead.

I had the great pleasure this past Wednesday of attending a satellite symposium of the International Society of Behavioral Ecology entitled Contemporary Research on Anuran Communication. Translated, that means that I got to go to a day of honoring some of the great minds in the field of frog communication.

The symposium was in New York City, at Hunter College, so I flew in on Tuesday to stay with a medical student friend who lives in the area. You might say that it seems a little excessive to fly across the country for one day, but 1) it’s not often that everyone in such a small field gets together, and 2) I have enough friends on the East Coast that I can justify a trip to see both the conference and them.

It’s taken me until today to let my brain digest all of the information it received on Wednesday, but I’m now in a position to tell you all about the highlights of the day, and all the amazing stuff that’s being done in frog communication these days!

Highlight the first: ROBOTIC TUNGARA FROGS (go watch this video, it is the best, I promise). Ryan Taylor at Salisbury University has done an amazing project with tungara frogs to see what kind of impact the visual signal of the vocal sac inflating has on female choice. See, sometimes male tungara frogs will involuntarily add a “chuck” sound to the end of their “whine” call, and this “chuck” is irresistible to the ladies. But if that “chuck” sound comes too long after the whine, it’s not appealing anymore. Additionally, inflation of the vocal sac isn’t attractive to females without any sound associated with it. But when you link the distant “chuck” to the “whine” by the inflation of the vocal sac between the two sounds (with the help of the amazing ROBOFROG!), suddenly it’s appealing again! The inflation of the vocal sac is acting as a kind of link to keep the female’s interest! So acoustic communication can be augmented by visual communication.

They didn’t make the robofrogs attack anyone or anything, though, to my great disappointment.

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Image courtesy of Lindsey Thurman.

Highlight the second: Susan Herrick‘s awesome talk on acoustic niche partitioning with green frogs and bullfrogs. Here in the Pacific Northwest, we hate bullfrogs for being ridiculously invasive, but where Susan does her research, they’re native. The two species call in the same frequency range, so there isn’t any partitioning there, and their breeding seasons fall during the same period of time. Bullfrogs are acoustically and physically dominant, so it falls to the green frogs to find ways to not overlap with bullfrog calls. It turns out that they’ll call in between bullfrog bouts and calls with surprising accuracy: they (statistically significantly) avoid overlapping with bullfrogs so they can be heard. It was a really awesome example of temporal acoustic niche partitioning.

Highlight the third: I MET MARK BEE. And shook his hand. And he said my study species (Pacific chorus frogs, Pseudacris regilla) are really interesting and he’s been meaning to do work on them!  His 2007 paper has been incredibly influential on my own research, and it was such a cool moment to actually say hello to him.

The honorees (5 of 6): Darcy Kelly, Kent Wells, Walter Hodl, Peter Narins, and Carl Gerhardt. Not pictured: Albert Feng.
The honorees (5 of 6): Darcy Kelly, Kent Wells, Walter Hodl, Peter Narins, and Carl Gerhardt. Not pictured: Albert Feng.

Highlight the fourth: all the little things. I got to learn a lot about frog perception and frog brains (did you know they don’t have cortices? I didn’t!), and how to test what frequency range frogs hear in. It was also amazing to be in the room with some of the greatest minds in frog communication, the researchers who started it all. The honorees were all very friendly (I got to chat with their wives a bunch) and it was both humbling and inspiring to be in the room with so many amazing people who love frog vocalizations just as much as I do.

All in all, it was a really valuable professional experience, and I made some good connections to move forward with. I look forward to presenting my own research to the people I’ve met someday!

Here at the ORCAA blog we try to bring you a glimpse into the everyday lives of our graduate students. Sometimes it’s really exciting and dramatic and involves cool technology, or going to interesting places with beautiful landscapes, or recording something new and important.

This is not one of those times.

Summer for many ecologically-based graduate students is a time for doing fieldwork, because the weather is (generally) better and you don’t have those pesky classes to get in the way. This is certainly true for many of my labmates, both in ORCAA and in the Garcia Lab, my other home. My fieldwork, on the other hand, is done in late winter-early spring, from the end of January until May.

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That’s right, I changed Songmeter batteries in the snow.

The weather was not nice for the most part, and the water was still really cold, but that’s when my study species, the Pacific chorus frog, comes out of the trees and calls to find mates.

I love studying amphibians. I love how complex their life cycle is, and the way that they make excellent environmental indicators (unfortunately, this usually ends up badly for them), and the way that they constantly surprise me. I really enjoy going out into the field to work with these little guys, even if it’s cold and inconvenient sometimes.

What all this means is that I spend my summers thinking.

Don’t get me wrong, I do other things too. I help my labmates with their experiments. I write, and I take classes, and I analyze data. I even take vacations occasionally.

As a student in the College of Forestry, I had a slightly different experience from the rest of ORCAA’s students when I started. One thing that was talked about at our two-day, sleepover orientation at HJ Andrews Research Forest was the value of thinking. Not of writing down while you think, not of talking with others and thinking aloud; the value of simply sitting and turning things over in your brain.

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Pacific chorus frog on a Songmeter

I’ve taken this to heart this summer. For all the time I spend deep in the nuts and bolts of analysis, I try to take an equal amount and spend it thinking about what this is telling me. I let my mind wander over the scope of my project and beyond, to what other people have done and what it means in the context of my own work, and even unrelated ideas for future projects. I can pass a lot of time like this, musing on this or that, but it always ends up being valuable in one way or another.

Sometimes I write things down. Usually I don’t.

In an age of deadlines, where everything is regimented and production is the way we measure success, sitting and thinking can be hard to justify. It’s hard to measure the tangible product of thinking, the new connections between ideas forged. But if we’re not encouraged to do this as graduate students, when we’re supposed to be finding new and exciting things, how are we ever going to do it as professionals? As professors? As researchers?

You’d be hard-pressed to find a field where a few moments of quiet thinking wouldn’t help you somewhere down the line.

So while I still have deadlines and analysis and things to produce this summer, I’ll take my time about it and do a lot of thinking as well—I figure, if not now, then when?

All of my labmates are currently at SeaBASS having an awesome time, while I am in Corvallis beginning the analysis of my data. It’s required a lot of thinking outside the box. So rather than talk about research or even strict bioacoustics, I thought I’d talk about something I find really interesting: sound design in the movies, and the way animal calls can be turned into something completely otherworldly.

I touched on this idea a couple of weeks ago with my fun link of the week to the sound design for the newest Godzilla, but Hollywood is littered with monsters galore with interesting roars. One of the most near and dear uses of animal sound in movies is the prevalence of choruses of my own study subject, the Pacific chorus frog.

When they’re trying to create a sort of nature setting in movies, sound designers often use clips of the Pacific chorus frog. It has that characteristic “ribbit” you want from a stereotypical frog, and you can hear the sound clip of it in places where the species definitely doesn’t live (I think I picked it up once in a movie that was set in Thailand. Yeah, no Pacific chorus frogs there.).

But why this particular frog? I mean, I personally love the way it sounds, but did sound designers pick it because of that? Turns out that’s not the case. Pacific chorus frog choruses are regularly featured in movies because early sound designers could go out to the ponds in California, even in the Hollywood area, and easily record the sound of the chorus. It was more a factor of convenience than desire.

There are some other stereotypical animal sounds that are often heard in movies. Every owl that you see (unless it’s a nature documentary) is probably going to have the call of the great horned owl, even if it’s not in fact a great horned owl. Now think about that sound that you hear whenever a bald eagle is shown onscreen, that piercing call—that’s actually a red-tailed hawk. Bald eagles sound more like this (follow the link).

What I find more fun is trying to pick out what vocalizations go into monsters. I’m kind of a big Lord of the Rings nerd, so naturally first we have to talk about Peter Jackson’s interpretations of the monsters there.

20130218015123!Orc_moriaThe Moria orcs (scrabbly little guys) have a really distinct high-pitched noise they make. Part of this sound is made up of the calls of some very vocal baby elephant seals, which sound designer David Farmer thought would be perfect after hearing them at the Marine Mammal Center in the Marin headlands. Do these guys sound like orcs to you?

The cave troll, too, had some animal vocalizations included, notably walrus and tiger. That sad moan when it dies comes from the walrus. Poor cave troll. I always felt bad for him.Cave_troll

To my everlasting dismay, we don’t know what dinosaurs sounded like: that kind of vibratory tissue just doesn’t fossilize well (with one notable exception: the duckbill dinosaur‘s oddly shaped crest may have been used to make sound). That doesn’t stop Hollywood from trying to recreate the calls of dinosaurs, however. Jurassic Park sound designer Gary Rydstrom used sounds from whales, lions, alligators, tigers, elephants, and even a koala to create the soundscape of the ill-fated imaginary park (this video of an elephant will convince you).

There are so many more monsters in Hollywood with their own signature noises. However, for the most part sound designers are pretty close-lipped about how they create their characters. And that’s really understandable. After all, if they didn’t keep some secrets, how could the new Godzilla sound so much more dramatic and scary than everyone else?

This post was brought to you with very little science and a lot of Googling. Some helpful sources are included below. Sound design isn’t a peer-reviewed field, remember. 

Main/Stock Sound Effects

Soundscape Explorations blog

Fellowship of the Ring Extended Edition

Movie sound effect origins

Soundbites is a (hopefully) weekly feature of the coolest, newest bioacoustics, soundscape, and acoustic research, in bite-size form. Plus other cool stuff having to do with sound.

Frogs change calling time in response to traffic noise: species with high peak frequency didn’t care about traffic noise, but species with low peak frequency optimized their calling to fall in lulls of traffic noise to avoid masking.

Researchers need to consider the costs of response to anthropogenic noise as well as benefits: we tend to focus only on the benefits of changing vocalizations in response to noise, but costs like increased predation risk, reduced transmission distance, and information loss need to be considered to get a balanced picture of trade-offs.

Fun link of the weekNPR looks at the technology and design behind the latest Godzilla’s roar (which in the past was done with a resin-coated leather glove against a double bass). With the emphasis on sounds recorded at higher frequencies, my guess is they got some high-pitched animal sound in there and slowed it down… thoughts?