Explore every episode of the podcast Music of Nature Podcast

Pigeon Roost at Picture Canyon - 17 May 2024, 7am, Picture Rock Canyon, Comanche National Grassland, near Campo, Colorado. Recorded by Lang Elliott. This is a binaural recording; please wear headphones. While exploring the Comanche National Grassland in southeastern Colorado, I visit Picture Canyon, known for its scenic vistas, unique sandstone rock formations, and prehistoric rock art. While I hoped to find something exotic to record, I instead stumble upon something mundane but welcome nonetheless. The high point is my discovery of a large communal roost of Rock Pigeons, nesting on ledges and in nooks and crannies along an extended sheer cliff rising about fifty feet above me. While this is the same species that is found in city parks around the world, I am thrilled by this rare opportunity to record their colony sounds, free of urban traffic noise and people talking. After spooking the birds, I hide in a clump of trees at the base of the cliff, and wait patiently for adults to return to their nesting site. Within a minute or two, several pigeons fly in, and before long the colony is alive with sounds. Pigeons coo while others arrive and depart in bursts of surprisingly loud wing claps and fluttering. It is satisfying to record these amazing sounds, much as they were heard thousands of years ago in rocky canyons and along oceanside cliffs across Southern Europe, North Africa, and Western Asia, long before the species was domesticated and eventually introduced to urban areas around the world.

Puffin Snorefest. 22 July 1994, 8am, Great Island, Witless Bay Ecological Reserve, Newfoundland. Recorded by Lang Elliott. In late July, I accompany two researchers to Great Island, a protected seabird sanctuary in Newfoundland’s Witless Bay. The island is the home to over 250,000 nesting Atlantic Puffins and the primary goal of my visit is to record their unusual buzzy snores, which sound like miniature chainsaws. This is not an easy project. The puffins nest in burrows in fragile grassy areas on steep slopes at the edges of sheer cliffs that drop straight down to the ocean. One slip and I might tumble headlong over the cliff and fall a hundred or more feet to the rocky shoreline below. To settle my nerves, I observe the puffins from a distance using binoculars and choose what looks like a good spot in front of a well-used burrow to place my microphone. Then I make my way to that location, causing many puffins to take flight. I step very carefully so as not to crush burrows or inhabitants hidden within. I place my microphone and then run nearly five hundred feet of audio cable back to our little research hut higher up the slope. From there, I patiently monitor the action through headphones. As expected, the puffins quickly return and soon there is a lot of vocalizing. What’s more, one puffin is very close to my microphone, standing at the entrance to its burrow and making for an exciting soundscape. All hail the Atlantic Puffin and its buzzy snoring call!

4/28/21 around midnight, Turkey Creek, Aravaipa Canyon near Klondyde AZ. NOTE: This is a ambient binaural soundscape; please listen with headphones! During a late April visit to the magical Aravaipa Canyon Wilderness Area in southeastern Arizona, I make my way to a remote side canyon where I camp under a large Cottonwood tree next to a small, gently splashing waterfall. The moon is full and a light fog hovers over the canyon. Around midnight, I am awakened by the distant melodic hoots of a Mexican Spotted Owl … hoo, hoo-hoo, hoo-oh. I also notice the sweet up-slurred whistles of a fledgling, presumably anticipating a tasty treat. The exchange continues for several minutes until another owl arrives and delivers the meal. The fledgling squeals with delight and then settles down. Serenaded by the fledgling’s whistles and the very distant hoots of one of the adults, I soon fall back asleep. A Note from Lang: This is perhaps my favorite Spotted Owl soundscape. While I have many close-up recordings of the species, I prefer this gentle ambient rendition because it invites the listener into the multidimensional listening experience itself … the sounds of the owls set against the spacious drippy splashes of the waterfall and the whooshy rush of the stream that drains the falls. And all this happens within the sheltered walls of a narrow desert canyon, with a full moon piercing the fog and illuminating the cottonwood, so freshly leafed and towering above.

Calming Crickets and Forest Drip - 25 September 2017, 1am, Shindagin Hollow near Brooktondale, New York. Recorded by Lang Elliott. As autumn begins revealing its colors, there is still a pleasing insect chorus at night in the forested hills of upstate New York. In late September, after an evening thunderstorm passes through the area, I visit nearby Shindagin Hollow in search of soothing meditative nightscapes. Well after midnight, the sky clears. A half-moon illuminates the forest, gently filtered through light fog. I stand silently next to a small ravine. Leaves are wet and dripping steadily. Tree crickets trill from all directions and spring peepers call sporadically, even though their breeding season is long passed. At times, a barred owl hoots from far in the distance, barely audible. I feel fully embraced by this lovely, nurturing soundscape. There is nothing to analyze, nothing to think about, nothing to hold on to. There is only a sense of deep immersion, complete surrender, and effortless communion with this extraordinary place and time.

In late June, I visit Olympic National Park and camp near Ozette Lake in the Olympic Peninsula. At the break of dawn, I amble along a trail leading to the Pacific Ocean and encounter an exciting constellation of sounds. Against a backdrop of subtle gurgles from a small stream and the gentle whoosh of a light breeze, two varied thrushes sing loudly from tall hemlocks while others sound off in the distance. Their vibrant, buzzy notes electrify the air. From the understory, a Swainson’s thrush sings prominently, its melodic flute-like notes sliding upward in pitch. A pileated woodpecker drums occasionally far in the distance. A band-tailed pigeon also chimes in, its hollow low-pitched coo-coo, coo-coo adding a pleasing musical element to the low end. And then, to top things off, a Pacific winter wren suddenly bursts forth with its high-pitched, liquid ramble exhilarating the mix.\ I rest against the trunk of a towering tree and take in this exquisite blend of sounds—a veritable audio fingerprint of the ancient old growth forests of the Pacific Northwest. Olympic Thrush-Tones - 23 June 2017, at dawn, near Ozette Lake, Olympic National Park, Washington. © by Lang Elliott, musicofnature.com

Muskrats Nattering. 31 August 2020, around 3am, Teeter Pond, Finger Lakes National Forest near Valois, New York. © Lang Elliott. In early autumn, I camp along the shore of Teeter Pond in the Finger Lakes National Forest in upstate New York. That night, crickets trill melodiously and katydids rasp their harsh chee-chee from the surrounding forest. In the wee hours of the morning, I awaken to whimpering notes and squeals, accompanied at times by water splashes. These are the sweet, endearing calls of muskrats. Listening carefully, I conclude that it’s a pair, sounding off as they swim along the marshy shoreline. The entire soundscape is pleasing, a soothing mix of insect songs, occasional frog calls, distant cattle mooing and bellowing, and, of course, the uplifting calls of the fun-loving mammals (I could be wrong here, but they sure do sound like they’re having fun). What could be finer than enjoying the nattering of muskrats as they slowly swim by, finally vanishing into the night? I take a long, deep breath and then gently drift back into sleep.

25 March 1994, 8am, Crescent Lake National Wildlife Refuge, Nebraska. Recording © Lang Elliott. In late March, I travel to Crescent Lake National Wildlife Refuge, located in west-central Nebraska, about twenty miles due north of the Platte River. It is early spring and the waterfowl migration is at its peak. Looking for recording opportunities, I home in on a long, narrow pond only ten or fifteen feet wide and perhaps a hundred feet long, with steep banks on each side. It is a waterfowl mecca, with ducks of several species excitedly swimming about while feeding. Still others streak by overhead, their wings producing loud, spine-tingling whooshes or musical whistles, or else they land with a splash. I dare not approach the pond because the ducks will scatter and might not return. So I wait until an hour before dawn the next morning, and under the cover of darkness, I place a soundscape mic in the middle of the pool. Fortunately, no ducks are present, but at first light they begin arriving and soon the pool is churning with activity. I can only imagine what my recording will sound like… Species to listen for: 1) Loud peeps given mostly in flight: Green-winged Teal. 2) Whistling wings while flying: Common Goldeneye. 3) Taking flight while calling chux-chux-chux: Northern Shoveler. 4) Otherworldly nasal calls (prominent at the end of the recording): Lesser Scaup. 5) Musical bird songs in the background: Western Meadowlark. 6) A loud raucous outburst followed wing flapping: Ring-necked Pheasant. A Note from Lang: This stunning recording was made by my dear friend and recording partner Ted Mack (now deceased) during our 6-month recording expedition way back in 1994. The above account summarizes how he described the experience to me.

June 6, 2021, 8:30pm, Cayuta Lake Outlet, Gulf Road, near Alpine, New York © Lang Elliott, musicofnature.com A lovely binaural soundscape-portrait of a Veery thrush singing and calling at dusk with the relaxing gurgle of a small waterfall to one side, the soft rush of a brook to the other, and various subtle bird songs in the background.

May 24, 2024, Buffalo Camp, American Prairie Preserve east of Zortman, Montana. © Lang Elliott. The most exciting section is near the end, from 3:35-4:00. CAN ANYONE HELP ME IDENTIFY THE MYSTERY SOUND-MAKER? My semi-educated guesses: How about Porcupine? I recorded this rather amazing mystery sound made by an unknown animal (presumably a mammal) in the American Prairie Preserve in Montana. At dusk, I set my microphone near the edge of Second Creek (47.7599103,-107.777872), just south of the Buffalo Camp campground. This unusual sound event occurred not long after midnight. Also evident are the loud song-phrases of a Yellow-breasted Chat, a common nighttime singer. Listen also for the hooting (and moans?) of Long-eared Owls in the background. NEWS FLASH: After some online sleuthing, I am now certain this is indeed a Porcupine. I found a great reference video on Youtube: https://www.youtube.com/watch?v=HpDtSjyTC6I

Light Rain and Forest Drip, 31 May 2021, around 3am, Cranberry Glades Botanical Area near Raintown, West Virginia. © Lang Elliott Recorded in the wee hours of morning along a swampy section of the boardwalk at Cranberry Glades Botanical Area high in the mountains of West Virginia. Raindrops and drips from trees splat against the broad leaves of skunk cabbage. Listen also for periodic spring peepers, distant barred owls, and the barely audible throaty gunks of green frogs in the background. To my ear, this is a wonderful relaxation track. Please set volume on the low side so that the splats of raindrops and drips are not too loud.

Kentucky Swamp After Dark - April 15, 1995 at 11pm. Land Between the Lakes, near Golden Pond, Kentucky. Recorded by Lang Elliott. Land Between the Lakes is one of our favorite locations for enjoying the sounds of nature. One year, we visit in mid-April and arrive just as the sun sets. The scene is exquisite, with a white-tailed deer silhouetted against the red sky. As darkness descends, we make our way to a swampy area next to a lake and are shocked by the number of whip-poor-wills, their repeated songs mixing with the bright notes of spring peepers and the chirps of field crickets. Great blue herons croak excitedly from the far side of the swamp, their raspy talkings lasting for quite a long time. We also hear the tail slaps of a beaver, chewing sounds, and the chuckling of distant leopard frogs. And that’s not all … a deer suddenly snorts and pounds its hooves against the ground, eventually bounding away. Minutes later, another does the same. What an amazing night chorus … so alive and full of sounds. We pray that generations to come will also behold such splendor, nature speaking in countless tongues!

Mountain Brook Nightscape - July 2, 2002, around midnight. Shindagin Hollow near Brooktondale, New York. Recorded by Lang Elliott. Please listen using headphones! In early July, I camp at the bottom of Shinagin Hollow in the Finger Lakes region of Upstate New York, a short distance from a small mountain brook. Around midnight, I am awakened by a distant Barred Owl that screams and hoots from the other side of the hollow. Other owls soon join in. The concert continues for over fifteen minutes, finally ending with a lone owl giving a slow-paced series of simple who-awl calls before disappearing into the night. I soon fall back asleep, once again surrendering to the soothing, everlasting gurgle of the brook.

Gentle Musical Waves. During an autumn trip to Lake Ontario in 2025, I was fortunate to encounter an evening of very calm wave action. Small swells rolled in, each lapping gently against round stones and producing an astounding variety of delicate, musical plinks, plops and splashes. It was as if the sea was having a good time making its water music and delighting at every turn. I sat quietly on a large rock nearby, fully immersed in the concert and quite taken by the relaxing yet engaging mix of sound. Recorded October 10, 2025 at Robert G. Wehle State Park, Lake Ontario shoreline, near Henderson Harbor, New York. © Lang Elliott.

Querulous Grebes at Raab Lake May 5, 1993, 4:30am. Raab Lake, Turtle Mountains, North Dakota. © Lang Elliott. With some difficulty, I make my way to the remote Raab Lake in the Turtle Mountains, along the border between North Dakota and Canada. The lake is nearly a mile long. All through the night, I hear the reverberant calls of red-necked grebes, but far in the distance, at the opposite end of the lake. As dawn approaches, the grebes finally come my way and put on a show I will never forget. Mated pairs call together in a duetting celebration, their trembling whinnies and brays blending with one another and echoing across the lake. Ruffed grouse drum loudly from nearby woods and a great horned owl hoots from the treetops. Though still quite dark, a song sparrow sings loudly time and again, as if heralding the coming light. People familiar with red-necked grebes might think their calls are dissonant and hard on the ears. But the querulous grebes of Raab Lake impressed me as being the opposite, their haunting, hypnotic melodies transporting me into a mystical realm of wonder and awe.

Recorded February 15-16, 2021 at Wolf Mountain Nature Center near Smyrna, New York. © Lang Elliott. I recorded throughout the night and this is a compilation of my best cuts of howling wolves, carefully sequenced for your listening pleasure. A gentle wintertime gurgling brook ambience has been added. Note: These are not wild wolves—they are the result of captive breeding programs at various locations across the continent. Wolf Mountain Nature Center is a registered 501c3 non-profit. The wolves are lovingly cared for by Wil Pryor (the Director) and the staff.

Wet Gloppy Snowfall. Recorded February 2, 2016, 10am. Connecticut Hill Wildlife Management Area, near Ithaca, New York. © Lang Elliott. It is early February in the Finger Lakes region of upstate New York. What begins as an idyllic snowstorm, with large, delicate snowflakes falling slowly and gently to the ground, quickly transforms as the temperature rises to well above freezing. The snowflakes begin melting before they hit the ground, turning into wet globs that splatter and smack as they strike the leaf litter. Such a unique, energetic soundscape, lying halfway between snowfall and rain! A Note from Lang: As always, recording rain is a challenge. In this case, I used my homemade rain setup, which consists of an open, cuboid frame wrapped in speaker cloth, with a thick layer of absorbent filters set on top. The goal, of course, was to record only the sounds made by the wet snow striking the leaf litter, while avoiding any sounds caused by melting snow hitting the mic frame itself or the absorbent filters above.

Beaver Moans and Cave Drip - 5min 24sec May 10, 2024, 11pm. Round Spring State Park, north of Eminence, Missouri. Recorded by Lang Elliott. In the Ozark region of southern Missouri, Round Spring wells up into a large sinkhole, surrounded by steep forested slopes on all sides. The water is a vivid blue and flows out through a cavelike passageway at one end, emerging about a hundred feet away to form the headwaters of a large creek that meanders a short distance before flowing into the Current River. With some effort, I am able to place my soundscape microphone a few feet into the cave, where drips from the ceiling and walls make resounding plops, plinks, and snaps as they strike water and stones below. I record the dripping sounds for several hours (see “Cave Drip” track). Then, at 11pm, something unexpected happens. I start hearing the mournful moans and whines, and later the chewing sounds, of two American Beaver. What a delight! Earlier in the day, I had seen beaver swimming in the creek below. with one heading upstream and disappearing into the cavern. Apparently, the beaver have a den inside the cave, or at least a bed of tree stems and small limbs from which they feed. A Note from Lang: Round Spring is a circular pool about a hundred feet across and 55 feet deep. The water flow is enormous—about 26 million gallons per day! The cavelike passageway is nearly twenty feet wide, but only two feet high at the entrance.

Gator Song - May 19, 2019, 1am. Anhinga Trail, Everglades National Park, Florida. Recorded by Lang Elliott. This is a binaural soundscape. Please listen with headphones for a spacious, immersive experience. In the middle of the night, along the Anhinga Trail boardwalk in the Everglades, I hear the gentle purring of crickets, a distant chorus of frogs, random splashes and pops, and chuck-will’s-widows chanting their night-songs. Then, quite suddenly, a surprise—I hear, and even feel, a sonorous, drawn-out growl, coming from nearby. It’s the unmistakable low-pitched mating bellow of a male alligator. Almost instantly, another joins in, and then another. The bellowing is clearly contagious. And then a male growls loudly from directly below me—he’s right under the boardwalk, no more than a foot or two from my feet! The bellowing continues for several more minutes, and then, just as suddenly, the alligators fall silent. Once again, all I hear are the songs of the crickets and frogs. NOTE: This recording has some very loud super low frequency content that will knock-your-socks-off if your headphones or speakers allow you to hear it.

Forest birds singing during mid-morning in the Sunklands area in the Ozark Mountain region of southern Missouri. Listen for the prominent wood thrush, plus carolina wren and yellow-throated warbler. Recorded 15 May 2021.

Dawn Chorus recorded at Chaparral Wildlife Management Area in south Texas, near Artesia Wells. 20 May 2005.

Dawn chorus at edge of a beaver pond in Shindagin Hollow, near Brooktondale NY. Listen for green frogs, bullfrogs and a variety of bird songs including: red-winged blackbird, wood thrush and mourning dove. Recorded 30 May 2013. Please listen with headphones.

A spirited dawn chorus along a marsh edge at Seney National Wildlife Refuge in the upper peninsula region of Michigan. Listen for mink frogs, green frogs, common snipe, american bittern, red-winged blackbird and much more. Recorded 8 June, 2004.

Varied Thrushes singing along a forest trail near Ozette Lake in the Olympic National Park. Listen also for a Swainson's Thrush and Winter Wren, along with the gentle gurgle of a nearby stream. 2 August 2021. Please Listen with headphones.

Magical Dawn Chorus at Spring Pond Bog in the Adirondack Mountains near Tupper Lake, NY. 12 June 2000. Listen for Swainson's Thrush, Hermit Thrush, White-throated Sparrow, Yellow-bellied Flycatcher and more. Binaural; please listen with headphones. © Lang Elliott, musicofnature.com

A pleasing dawn chorus recorded at Connecticut Hill Wildlife Management Area near Ithaca, NY. 21 May, 2016. Binaural - Please listen with headphones. Prominent singers include Eastern Wood-Pewee, Mourning Dove, Wood Thrush, Rose-breasted Grosbeak, and Ovenbird. © Lang Elliott, musicofnature.com

Birds at dawn. Connecticut Hill Wildlife Management Area near Ithaca, New York. © Lang Elliott, musicofnature.com

A soothing binaural ambient recording featuring forest drip at dawn with Wood Thrushes singing from all directions and crickets trilling. Listen also for several hoots from a Barred Owl. How nice to hear so many Wood Thrushes singing together in a chorus, especially given that populations have been steadily declining over the last fifty years. Recorded 23 June 2024 in Mammoth Cave National Park. © Lang Elliott, Music of Nature. Please listen with headphones.

A 19-minute binaural nature podcast describing my "nature sound adventure" at Land Between the Lakes, Kentucky, in mid-October 2019. For an immersive 3D listening experience, please use headphones! © Lang Elliott, musicofnature.com

A fully binaural 30-minute podcast featuring 23 nature soundscapes from the Yasuni National Park region in Ecuador's lowland rainforest (at the wonderful Sani Lodge). All recordings were gathered during the first week of November, 2018. Please use headphones for a fully immersive listening experience! In this nature sound experience, I share my rainforest recording adventure, condensing nearly six days of field work into a reconstruction of a typical day of observing and listening. The soundscapes that are featured can indeed be experienced in a day. Not so with recording ... it's far easier to listen than to actually capture the soundscapes. That said, I am quite happy with what I managed to get, although I sure wish I could have stayed for another few days. As an aside, the guides at Sani Lodge, all indigenous, were terrific. Not only did they know the sounds of virtually everything, they were also wonderful imitators, quite often singing back to the birds, for the sheer joy of it. © 2018 Lang Elliott, musicofnature.com. All Rights Reserved.

This binaural podcast features recordings I made during the month of May in 2018, at the height of spring near my home in upstate New York. Please join me on this nature sound adventure, and be sure to listen using headphones for a fully spacious experience. This is the first in a series of two or three podcasts wherein I will share my best recordings from 2018. Because of project deadlines that kept me glued to my computer, I did not get out much this season. But that will change next year, when I plan to head to Florida in early spring and then follow spring north, perhaps all the way to the Gaspé!

Delayed Spring — A Binaural Podcast by Lang Elliott The great warbler migration is upon us here in Ithaca, on this fine warm day of May 3rd. But the ten days between my last blog post and today were not the greatest, weather-wise or bird-wise, with lots of cold days, freezing nights, rain and wind. It even snowed one afternoon! Nonetheless, I gathered recordings of 21 species on four different days and I've put together this new podcast ... Delayed Spring ... to celebrate what I found. About twenty minutes long, the podcast features quite a number of deliciously spacious binaural soundscape recordings. So, if you listen with headphones or earbuds, you may very well think you're out in nature with me, fully immersed in the 3D sound environment. Note that I've made a special effort to include long intervals where you just hear the sounds of nature, rather than me gabbing about it all. What follows is a list of the 21 species featured, roughly in the order in which they are presented in my podcast: Wood Frog, Spring Peeper, Blue Jay, Whie-throated Sparrow, Swamp Sparrow, Black-capped Chickadee, Dark-eyed Junco, Louisiana Waterthrush, Hermit Thrush, Eastern Phoebe, Blue-headed Vireo, Yellow-bellied Sapsucker, Belted Kingfisher, Mallard, Yellow-rumped Warbler (I think), Eastern Towhee, Field Sparrow, Red-winged Blackbird, Downy Woodpecker, Northern Mockingbird, and American Toad. I hope you enjoy the show!

An impromptu podcast featuring nature recordings I made in my backyard on April 22, 2018. I used a Telinga stereo parabola. The Story: I got up early on Sunday (April 22) to see how many birds I could record with my trusty parabolic microphone. I was expecting perhaps a dozen or so, given the difficulty of getting decent recordings. As it turns out, I ended up recording a whopping 26 species … 24 birds, 1 frog and 1 mammal, all found in my own backyard (I never left our property). Luckily, we have a number of habitats, which helps for sure, including: a pond with some cattails, grassy meadows, lots of shrubby edges, an overgrown field, and forest. Returning to my studio the next day, I set about editing the recordings and throwing together a narrative, which I performed off-the-cuff, without writing down any script. I rather like the result … uncomplicated, straightforward, and without too much talking. I was lucky to have gotten so many recordings, which makes for a compelling little bird walk, so suitable for celebrating the dawn chorus on an early spring day.

"Meltwater Melodies" is an 11-minute long binaural podcast by Lang Elliott. Please use headphones for a superb 3D listening Experience. In this podcast, I share my recording adventures while visiting the Three Sisters Wilderness Area in the Cascade Mountains of Oregon during the summer of 2017.

"Desert Sojourn" is a 25-minute podcast featuring binaural nature recordings that I gathered in Organ Pipe National Monument (southern Arizona) in late March of 2017. Please listen using headphones or earbuds for optimal immersive effect. Featured species include: Elf Owl, Great Horned Owl, Western Screech-Owl, Common Poorwill, Greater Roadrunner, Gambel's Quail, Gila Woodpecker, Cactus Wren, Ash-throated Flycatcher, Northern Mockingbird, Curve-billed Thrasher, Scott's Oriole, Black-throated Sparrow, Canyon Towhee, House Finch, Windblown Cactus, Bee Buzz, Crickets, and more!

"Big Bend Sound Delights" is a 21-minute audio podcast commemorating my early to mid March visit to Big Bend National Park in Texas. Along with bees buzzing, great insect choruses, and the gurgling of the Rio Grande, enjoy the songs of Canyon Wren, Cactus Wren, Mexican Jay, White-tipped Dove, Greater Roadrunner, Great-Horned Owl, Elf Owl, Western Screech-Owl, and more! © 2017, Lang Elliott, musicofnature.com

"The Voices of Lost Maples" podcast documents my early March visit (with my field assistant Beth Bannister) to Lost Maples State Natural Area in the Hill Country of Texas, about 80 miles northwest of San Antonio. Features Barking Frogs, Great-Horned Owl, White-tailed Deer, Eastern Phoebe, Carolina Chickadee, Canyon Wren, White-tipped Dove ... and more!

An audio podcast commemorating my early March visit to the Lower Rio Grande Valley of Texas. Features the voices of Common Pauraque, Chachalaca, Green Jay, Great Kiskadee, Eastern Screech-Owl, Long-billed Thrasher, Golden-fronted Woodpecker, and more!

Lang's first audio postcard (podcast) from his 2017 Nature Soundscape Recording Expedition. Featuring recordings from the coastal marshes of Louisiana made from February 26 through 28.

This is the introductory trailer for Lang Elliott's forthcoming Music of Nature Podcast Series.