Building the Archive
How you can help

The Macaulay Library was built from the ground up from the contributions of hundreds of recordists. Contributors do not fit one profile, but come from many different backgrounds and interests. Following in the footsteps of the founding recordists, whose dedication and creativity inspired hundreds of recordists, we seek collaboration from many sources. Some of the most enthusiastic contributors are our staff, and we are indebted to a growing number of outside audio and video recordists.

Our goal is to build the most comprehensive collection of animal sound and video as possible, but we cannot do it without the support of recordists worldwide. Being a professional recordist is not a prerequisite for contributing. Our material comes from recordists of all backgrounds and occupations, from students to retirees, from "bird bums" to researchers, dentists, consultants, and cinema photographers. We are continually grateful for the dedicated, talented, creative, and generous people who have donated their time, recordings, and other resources in support of the archive.

There are still many recordings on our Most Wanted List we are working to add to the archive. Please contact the library if you would like us to archive your recordings.

How to Contribute

We’re interested in hearing about your collection, whether you have a handful of recordings of a unique species or years worth of material. Please contact us to let us know that you are interested in submitting your recordings and we will get back to you.

It is important to note that upon submitting recordings, you enter a partnership with the Macaulay Library/Cornell Lab of Ornithology. We ask recordists to sign an archival licensing agreement that sets the specific terms of archival between the Macaulay Library and the contributor. Some terms of this agreement are negotiable. Please contact us to discuss the details of our Archival agreements.

What We’re looking For

Whenever possible we archive original files or physical media in the highest-resolution format available. For example, if your recordings were made on cassettes and later digitized, we are still interested in having the original cassettes.

Recordings with detailed metadata are generally more valuable as archival specimens. The species name, the date and the location are the most important pieces of metadata that we keep track of. However, we also keep track of time of day, age of the subject(s), sex of the subject(s), behaviors of the subject(s), recording equipment, if playback was used, details of habitat and other pertinent notes. The process of organizing your recordings and associated metadata can be time consuming and monotonous. Review the tips below to make the process a bit easier.

  • We recommend using a spreadsheet or field notebook to keep track of associated metadata
  • For audio recordings: When in the field, make an announcement at the end of every track. Report information about the subject, recording conditions, date, time and location whenever possible. Report that the track is “junk” to indicate that it should be deleted. Announcement data can easily be added to a spreadsheet at a later time.
  • If using a digital audio recorder or video camera, set the date, time and file name on the recorder before your recording sessions. Check the manual for your equipment for specifics on how to do this. Most manuals can be downloaded online if you do not have a copy. This can save you a lot of time when organizing your recordings later.
  • It is often easiest to review files chronologically, so choose a naming scheme that allows you to sort chronologically. For example “JHB20100308_0746_001” includes the initials of the recordist (JHB), the date (8 Mar 2010) and the time (7:46 AM).
  • Take hand-written notes where necessary. Make sure those notes can be tied back to the cut, track, or file name of each recording.

Review our Audio Techniques and Video Techniques sections on the Field Recording page for tips to help enhance the overall quality of your recordings.

One of the most common questions posed to us is: "Does the Macaulay Library really need any more recordings?" And the answer is yes. Even in North America, there are still opportunities for recordists to contribute either the first archived recording or the first high-quality recording for a species, and this is to say nothing of specific sounds for many more species. Make your mark in the annals of ornithology! The following list represents the 15 most-wanted North American species for the audio collection:

  • Steller's Eider
  • Surf Scoter
  • White-winged Scoter
  • Masked Duck
  • Arctic Loon
  • Clark's Grebe
  • Northern Fulmar
  • Great Cormorant
  • Red-faced Cormorant
  • Aplomado Falcon
  • Little Gull
  • Iceland Gull
  • Lesser Black-backed Gull
  • McKay's Bunting
  • Shiny Cowbird

If you have recordings of any of these species from North America that you would like to archive at ML, or if you could be in position to record one of these species in the future, please contact us at or (607) 254-2404.

In addition to our "Top 15" list, we are also seeking high-quality recordings of specific vocalizations of some other North American species:

  • Ross's Goose (flock)
  • Hooded Merganser (male display)
  • Common Merganser (male display)
  • American Bittern (flight call)
  • Cooper's Hawk (wail)
  • Sharp-shinned Hawk (wail)
  • Red Knot (flock)
  • Black-billed Cuckoo (song)
  • Gilded Flicker (drum)
  • Northern Shrike (song)
  • Philadelphia Vireo (call)
  • Gray Catbird (rattle)
  • Brown Thrasher (call)
  • Golden-winged Warbler (call)
  • Palm Warbler (calls from both Western and Yellow groups)
  • Ovenbird (flight song)
  • Common Yellowthroat (flight song)
  • Lark Bunting (call)
  • Nelson's Sparrow (call)
  • Saltmarsh Sparrow (call)
  • Hoary Redpoll (song)
  • American Goldfinch ("potato chip" flight call)

There are even more opportunities for contributing recordings from outside of North America. We currently have recordings for more than 7,500 bird species from 150 countries around the world, but that still leaves about a quarter of the world's birds to be recorded! We welcome new recordings from all over the world, and are especially interested in adding to our collection of recordings from Africa and Asia.

These downloadable Excel files contain target species lists for broad geographic areas around the world. The lists, based on checklists from Avibase, include all species for which ML currently has fewer than five recordings playable on

We can also provide country-specific target species lists, so if you're planning on recording in a particular country or region, please e-mail us at We would be happy to prepare a list of possible target species for your recording efforts.

Video Most Wanted

The Library's video collection contains a wide variety of bird behaviors, but there are many aspects of the lives of birds that need further coverage. If you have recordings of any of the following species that you would like to contribute to the archive, please contact us.

The Hit List:

  1. Black Noddy (Anous minutus)
  2. Red-necked Stint (Calidris ruficollis) 

  3. Eared Quetzal (Euptilotis neoxenus)
  4. Yellow-bellied Flycatcher (Empidonax flaviventris) 

  5. Golden-winged Warbler (Vermivora chrysoptera)
  6. Hermit Warbler (Dendroica occidentalis) 

  7. Cerulean Warbler (Dendroica cerulea)
  8. Olive Warbler (Peucedramus taeniatus)
  9. Pinyon Jay (Gymnorhinus cyanocephalus) 

  10. Brown Jay (Cyanocorax morio) 

  11. Brown-headed Nuthatch (Sitta pusilla) 

  12. Aztec Thrush (Ridgwayia pinicola) 

  13. Saltmarsh Sparrow (Ammodramus caudacutus) 

  14. Varied Bunting (Passerina versicolor)
  15. McKay’s Bunting (Plectrophenax hyperboreus)

We are particularly interested in new video of nesting activities (nest-building, incubation, feeding of nestlings), swimming underwater, diving (prey capture in Osprey, Gannet, Kingfisher), as well as other birds of prey hunting and capturing prey. Anyone with a strong interest in filming and recording nature is well suited to assist in our efforts.

Please contact us if you are interested in submitting video or if you would like to learn more about opportunities for instruction in field technique and the possibility of borrowing high quality recording equipment.


The Macaulay Library regularly undertakes recording expeditions to increase the breadth and depth of vocalizations and behaviors in the archive. In recent years we have targeted regions with a high diversity of species that are not yet well covered. See our Big Year Expeditions website detailing our efforts in 2007 to record North American birds in Alaska, Florida, Nova Scotia, and Texas. Between 2008-2010, expeditions visited the Canadian Arctic, Guatemala, South Carolina, Texas, western Mexico, the Great Basin and the Louisiana Gulf coast. Some of our most recent expeditions are detailed below.

Recent Expeditions

Channel Islands Seabird recording: In 2010, Assistant Curator Benjamin Clock carried out a recording expedition to California’s Channel Islands National Park to record the night chorus of breeding Alcids and Petrels on their offshore breeding rocks and inside sea caves. Several nights were spent in the islands gathering recordings of Ashy Storm-Storm-Petrel and Cassin’s Auklet as they arrived at the breeding caves and Xantus’s Murrelet around the periphery of the breeding colony recorded from a kayak.

PNG Bird-of-Paradise filming and recording: In 2010, Video Curator Edwin Scholes and collaborator Tim Laman conducted three month-long expeditions to document Birds of Paradise in New Guinea and Australia. Target species, most of which were new for the Macaulay Library included: Splendid Astrapia, Twelve-wired Bird of Paradise, Pale-billed Sicklebill, Long-tailed Paradigalla, Greater Bird of Paradise (from the Aru Islands), Wilson’s Bird of Paradise, Red Bird of Paradise, Paradise Riflebird, Short-tailed Paradigalla, King of Saxony Bird of Paradise, Ribbon-tailed Astrapia, and Raggiana’s Bird of Paradise. This work, which is part of the Bird of Paradise Project co-led by Scholes and Laman, is a significant contribution to the most comprehensive collection of bird of paradise video in the world.

Click here to support recording expeditions or contact Scott Sutcliffe at (607) 254-2424.

Audio Curation


Species Reels

The collection storage room is designed specifically to house our audio and video media. With limited access and specialized shelving, coupled with strict temperature and humidity control, we ensure an ideal environment for the long-term storage of magnetic tape, thereby maximizing the life of the recording medium.


Aside from simply documenting who made a recording, identifying the species, and noting where and when the recording was made, we also store valuable information on the recording equipment used, detailed behavior and habitat descriptions, and weather conditions. We make an effort to supplement information not originally noted by the recordists by consulting experts to note additional information, such as the the call type or identifying other species vocalizing in the background.

Protocols for consistency

Open Species Reel

Over the years, the Macaulay Library has developed protocols to ensure uniformity in the way each recording is preserved as a 'specimen' and associated data are stored. The goal is, if an archivist from 1960, 2004, or 2040 were to be given the same field recording, all would generate nearly identical specimens. While advances in technology have and will alter and expand the way in which the work is done, the essence of the archived specimen should remain consistent.


Tape Restoration Room

Over time, problems develop with recording media in both analog and digital formats. For example, tapes may become sticky and/or shed, causing the oxide (material the sound is stored on) to separate from the tape backing, resulting in lost information that can never be reclaimed. Tape stocks may also dry out and become brittle, making playback without damage nearly impossible. We have the expertise and facilities on-site to temporarily correct many of these problems, thereby allowing us to digitize otherwise unplayable recordings.

How does the digital archival process work?

Archival Studio

Audio field recordings are put into a digital editing system at sampling rates of either 96 kHz or 192 kHz and a depth of 24 bits, using either Prism Sound or dCS analog to digital converters. While these may seem like extraordinarily high sampling rates for many species, it provides unparalleled fidelity, signal resolution, and the ability to handle many of the ultrasonic signals produced by toothed whales, bats, and other wildlife.

Specimen creation and editing

After putting the raw field recording, the archivist uses standardized protocols for determining where one specimen ends and another begins. Some example criteria used for these decisions are whether the recording equipment was turned off and for how long, or whether the species or the individual of interest during a recording changes. The field material is edited into audio specimens with a powerful digital sound-editing program, SonicStudioHD. After identifying the specimen on the original field recording, the archivist assigns a catalog number, adds a voice announcement of the catalog number, digitizes the desired audio segment, and optimizes the amplitude of the sound of interest. Other than level optimization, archivists strive to maintain the specimen as it came from the field. No additional manipulation of the sound occurs and filtering is used only when the amplitude level setting on a particular sound is challenging due to low-frequency interference, such as from wind or equipment handling.

Data entry

The associated data record for each audio specimen is created by the archivist, mostly from information provided by the recordist. Using the recordist's notes, the archivists enter precise information on time and location, habitat description, behavioral context, equipment setup, and any other information available. Data are stored in a relational database, allowing powerful searches on multiple fields and text entries.


The output of the digitization process is high resolution (96 kHz/24-bit) AIFF audio files, which are written onto two, first-generation DVD-ROM discs. One DVD is stored on-site, and the second serves as a safety copy that is sent to a secure, off-site, climate-controlled facility. The high-resolution files are also down-sampled into more readily accessible and more easily-distributed lower resolution formats such as .wav, .mp3, and QuickTime.

Storage and Delivery

After a batch of recordings are processed the archivist exports the tracks (named by catalog number) as high-resolution (96 kHz/24-bit) BWF files. The high-resolution files are transcoded into a 44.1KHz/16-bit wav and MP3 file formats. The MP3 versions are moved to a server that allows for instant web access. The 44.1/16 wav files are ready to fulfill client requests. The high-resolution files are stored on an Apple Xserve/X-RAID array with a 70-terabyte storage capacity. In addition, two DVDs are burned containing the high-resolution files. The DVD’s are analyzed using an AudioDev CATS DVD-R/RW Pro audio system to ensure that they meeting industry standards. One DVD is stored on-site and one is sent to a secure, underground storage facility in Pennsylvania.

Quality control

Studer close-up

Quality control is a critical part of our archival process. Archival studio equipment is frequently calibrated to known International Standards. Internal operating protocols are in place to ensure consistent quality standards, throughout the archival process. Additionally, archivists double-check each others' work after archiving a body of recordings. The storage media (DVDs) are also quality control checked pre- and post-writing. All DVD-Rs are analyzed by using an AudioDev CATS DVD-R/RW Pro audio analyzer system to ensure that they meet or exceed industry standards. Discs that either fail or are of marginal quality are rejected. To monitor the stability and longevity of the digital archive, DVD discs are randomly selected and re-tested. We then compare test data from initial disc creation to current tests, looking for any signs of change or manufacturing batch-related problems.

Video Curation

In 2001, the Macaulay Library became a more diverse multimedia collection by making a concerted effort to seek out and archive video for the first time. Film has been a small component of the archive from its very early days, but today it holds over 3,000 reels of various film and video formats. To date, between one third and one half of the reels acquired have been digitized.

In recent years, a trend towards tapeless, digitally born (DigiBorn) video has required some alternative workflows that largely parallel the processes described below for tape-based media. Differences in workflow are described as necessary, denoted by an asterisk.

Archival Agreement

Before receiving or accepting video material from a contributor, the curatorial and archival staff must carefully consider the commitment of storing, preserving, and archiving the material in perpetuity. When it’s agreed that the material should be accepted for archival, an archival agreement with the contributor must be completed. This agreement is the contract that sets the specific terms of archival between the Macaulay Library and the contributor, including any restrictions and/or sub-licensing rights.


Upon receiving video material from a contributor one of the first steps in the archival process is to enter several pieces of information about the material into our accessions database. Media (tape or film reels) received from a contributor (individual or institution) at one point in time generally constitutes an ‘accession’ and receives a unique accession number. For each reel in an accession the date(s), the location(s) and the recordings subject(s) are recorded. Media format, media generation, storage location, technical notes and notes about condition of the reel are also recorded during the accessions process. At this point we assign a unique alphanumeric code for each reel (the “ML reel number”) and labels with the reel number are then applied to each unit (i.e. tape, film reel, disk, etc). The accessions process and resulting reel numbers allow us to track individual media units within the physical storage space. The reel number is also used to track digitized reels and related project files throughout the course of the entire archival process.

* When accessioning DigiBorn video, the archivist will parse the sometimes numerous video files into ‘reels’ based upon dates and locations of the recordings. Files from one reel are moved to a single folder, named by the ML reel number convention, and then moved to an offline hard disk, which is stored in the physical storage space like an actual media reel. An identical backup is placed on a second hard disk for redundancy in the unlikely event of disk failure.


All physical media is stored in a climate-controlled facility, designed specifically to preserve the life of original analog materials. The temperature and humidity in the physical storage area are set to specific levels to minimize the degradation of magnetic tape.


After the accessions process, the next step is to digitize or ‘encode’ the tape-based media. To process motion picture film, transfer to videotape using a process called Telecine is required first – this process comes at a relatively high cost through an external Telecine service. Macaulay Library has in-house hardware to handle several videotape formats including: HDCam, HDV, DVCam, DV, MiniDV, Digital Betacam, BetacamSP, Hi8, Video8, VHS and SVHS. The appropriate tape deck is used in conjunction with an AJA IoHD media converter and an Apple Mac running Apple’s Final Cut Pro video editing software. Using this equipment, the entire reel (or usable portion) is digitized using the ProRes 422 codec (a compressor/decompressor algorithm), which produces a compressed, but visually lossless, image for archival. The full digitized reel (or master encode) is retained as a digital duplicate and is stored on an offline hard disk, whose contents are cataloged and managed in the accessions database. As part of the digitization process a Final Cut Pro project file is created for every reel and named by the associated ML reel number.

* DigiBorn videos, by definition, do not require digitization. However, most DigiBorn videos are in a ‘native’ codec other than ProRes 422. In the interest of consistency throughout the archive we convert all DigiBorn material to the ProRes 422 codec in a process called transcoding, which is a computer intensive ‘translation’ process whereby one codec is converted into another.


When a reel has been digitized it can be broken up into discrete subclips that end up as individual assets, or video specimens, in the digital archive. This is part of a process called logging. By opening a Final Cut Pro project file the archivist can play back and review the associated master encode. Frame-by-frame control of the master encode is possible and the temporal limits (start and stop) of each subclip can be defined (i.e.- edited). Archivists edit subclips based upon video qualities (focus, frame, smoothness, etc.) as well as content (species, behaviors, etc.) As they are defined and selected as assets, the subclips are listed in a browser window within Final Cut Pro. There, additional metadata including date, locality, subject, behavior and equipment data can be recorded in columns of the browser window. When the entire reel is logged and all usable subclips are defined they are given unique catalog numbers and then exported. The exported subclips retain the ProRes 422 codec and other inherent video qualities of the master encode. Other editing techniques like video filters are rarely used so as to maintain the original quality of the recording. The exported files are, of course, shorter in duration than the master-encode and they are named using the ML catalog number convention.

* For DigiBorn material the logging process is generally quite similar. However, there are some key differences. First, with DigiBorn material the Final Cut Pro project file will reference several digital video files that make up the reel instead of the single master encode. The same editing techniques and criteria are used with these multiple video files. However, most DigiBorn clips are quite short and they do not generally require subclipping – many clips are exported without making changes to the duration at all.

Archiving and Transcoding

After being exported the subclips officially become Macaulay Library video specimens by moving them to the archive volume on an Apple X-Serve/X-RAID array. The archive volume has a capacity of around 55 TB and the entire video archive amounts to about 13 TB at the start of 2011. The content of this high quality archive can be accessed within the Macaulay Library by an application called Final Cut Server. Final Cut Server is a relatively new, but powerful, media management application that allows you to sort and search media files in a variety of ways.

So that streaming of data-intensive video files is possible over the Internet, a lower resolution “web proxy” version of all archived assets must be created. All assets are transcoded to a proxy version using a codec with greater compression, which translates to smaller file sizes and ability to be played through a web-browser via the internet. And so, in addition to the high quality archive, there is a parallel proxy archive that can be accessed through the Macaulay Library website.

Data Entry

Each cataloged video asset has an associated data record stored in Macaulay Library’s Oracle database, which is accessed through a custom-built online data entry application (currently only available to Macaulay Library staff). This data record includes much of the same recording-specific metadata that is entered into the browser window in Final Cut Pro, including the taxonomic identification, date recorded, geographic location, and life history and behavioral information. Additional recording-specific details and annotations are added on a record-by-record basis. Most of these data are available through the cataloged video specimen record on Macaulay Library website along with the proxy version of the recording described above.

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