Sjoerd Mayer studied mathematics on the University of Enschede in the Netherlands. In those days (1970’s) computers were introduced to universities, and Sjoerd, in his 20s, was already exploring new possibilities of combining his hobby, birdwatching, with mathematics. According to him it was possible to store a sound of a bird on a computer. He once proudly showed his birder friends a floppy disc that contained the sound of a bird, according to him. He could not prove it because the mainframe computer in the basement was not able to play sounds. But Sjoerd was convinced there were possibilities in doing 'something' with birds and computers.


After his study (cum laude) and military service, Sjoerd was asked to work for the Natlab of Philips in Eindhoven. He was taught to write computer programs and after having worked writing software for a few other companies, he decided to work independently writing software for third parties. Sjoerd made a good living, and he decided to combine his work with traveling. He made long, strenuous trips of sometimes several months to countries like Nepal, the Philippines, and Bolivia.


Bolivia stole his heart, and in the late 1980s Sjoerd decided to live partly in Santa Cruz.  He roamed Bolivia, but also lived in Holland part-time with his mother. In the beginning he lived with his friend Bernard Geling in Santa Cruz, who accompanied him on several exciting trips. In the early 90s Sjoerd started recording sounds of birds on cassettes with a Sony professional Walkman. He spent many hours recording birds in the field and at home replaying the sounds and annotating the information in small notebooks. He had a tremendous skill for remembering the sounds, and soon he discovered that the songs of the birds were very important in identifying the species, sometimes more important than the illustration and description in the field guide.


Sjoerd always kept his computer knowledge up to date by writing software for companies such as the Dutch Railway (NS). In Santa Cruz he bought computer magazines from the small newspaper stands on the street. One day in 1994 he read an article about using music on computers. He came up with the idea of importing his sound recordings into a desktop computer. Because there was not much sound software around, Sjoerd started writing his own computer program using his programmer skills. When his friend Bernard saw what he made, he immediately saw possibilities selling CD-ROMs with sounds of birds to the birders visiting South America.


In 1995 Sjoerd and Bernard decided to start the company Birdsongs International. Their goal was to sell sounds of birds to the public; their first publication would be about the birds of the country where both their hearts were: Bolivia.  Sjoerd went on to record the sounds of as many bird species as possible in Bolivia, while Bernard was doing the paperwork to found the company in the Netherlands. In December 1995 Birdsongs was legally established, and soon the first publication on a CD-ROM became available named "Bird Sounds of Bolivia/Sonidos de Aves de Bolivia version 1.0". Sjoerd made all the recordings and wrote the software. Bernard was the man in Holland who did the reproduction, sales, shipping and administration of the small company.


Although the sales figures were not high, the innovative product was well received in the birding community. Birders with collections of sound recordings on tape wanted to cooperate.  Some contributed their recordings to the Bolivian project, and others asked Sjoerd to make new publications. Peter Boesman produced with "Birds of Venezuela", Jelle Scharringa made "Birds of Tropical Asia”, and Niels Krabbe and Jonas Nilsson produced "Birds of Ecuador". Sjoerd added illustrations and ingenuous distribution maps (Tropical Asia).  He continued to develop software, and soon second DVD-ROM editions were made and even a third DVD-ROM edition for Tropical Asia was published.


To sell the products internationally, Sjoerd made a website where birders from all over the world could buy the products. Again he showed his software talent by making a fully functioning web shop with shopping basket, credit card payment feature, etc. several years before web shops became mainstream ways of selling products. Developing new bird song productions took more time then expected, and costs were soaring. The web shop had only a few products, and to boost sales Sjoerd and Bernard decided to start selling other sound productions. The French recordist Jean Roche cooperated by selling his CDs of the Birds of France in their shop. Soon several other recordists added their CDs, and the web shop became well known in the international birding community.


In the early 1990s Sjoerd started complaining about a numb leg during his strenuous bird trips he made in the jungle and mountains of Bolivia. He went to see a physiotherapist, but it did not solve complaints. On one of his periods in Holland in 1996 he went to see a doctor who diagnosed Multiple Scleroses. It did not stop him from going to Bolivia: the very next day after the doctors gave him this very bad news, he was on a plane to Bolivia. He was in love with a lovely young Colombian girl named Nieves, whom he met in Santa Cruz. They decided to marry and live in Cochabamba, where their first child was born. Unfortunately, Sjoerd's health deteriorated faster than expected, and for medical reasons they had to go and live in Holland.


Once settled again in the Netherlands, Sjoerd decided to devoid all his working time to developing his software and selecting sound recordings. He spent many hours listening to recordings that other sound recordists sent to him. His desk was littered with hundreds of tapes to which he listened extensively and from which he made meticulous cuts that could be used on a new version of his 'Birds of Bolivia'. He had enough material to cover the sounds of nearly all the birds of Bolivia, southern Peru, and Paraguay, a production that unfortunately has never been published.


Sjoerd's health was deteriorating, and the family was forced to move to a specially adapted house where Sjoerd got his own room in which he could move freely with his wheelchair. After roaming much of South America, he now divided his precious remaining time between his computer room with his sounds and the living room with his wife and kids. To become eligible for income security for his years left, Sjoerd was forced to give up Birdsongs International, to his great regret. MS was affecting him in a bad way physically as well as emotionally.


At the end of his life Sjoerd decided to make drastic decisions, clearing up his adventurous life he decided to throw away everything of his past, literarily in a dustbin. Done with that, he started seeing off his best friends, sometimes in a not such a nice way. He isolated himself from the outside world and devoted more and more time to his family. He was very lucky in having a wife like Nieves, who helped him all she could. The last words on Sjoerd's website were more then true: "I'd already be in a nursing home by now if it weren't for my brave wife Nieves. The show is (almost) over!"


Sjoerd Mayer was co-founder of Birdsongs International, the company that developed and sold CD- and later DVD-ROMs of Bolivia, Venezuela, Ecuador, and Tropical Asia.


Bernard Geling, August 2012



Sjoerd Maijer bibliography


Compiled by Frederik P. Brammer, October 2012:  I would be grateful for additions and corrections – please send to: frebram at gmail dot com


In chronological order.

Kennedy, R. S., Mayer, S. & Fisher, T. H. (1984): Notes on Philippine birds, 3. First sight records of the Javan Pond-Heron Ardeola speciosa from the Philippines. Bull. Brit. Orn. Club 104: 102-103.

Mayer, S., Christiansen, M. B. & Pitter, E. (1993): Birds observed along the road Vallegrande-Masicurí, dpto. Santa Cruz, Bolivia, in 1992 and 1993. Unpublished report.

Mayer, S. (1995): First record of Giant Snipe Gallinago undulata for Bolivia. Bull. Brit. Orn. Club 115: 188-189.

Mayer, S. (1995): Notes on the occurrence and natural history of Berlepsch's Canastero Asthenes berlepschi. Cotinga 3: 15-16.

Fjeldså, J. & Mayer, S. (1996): Recent ornithological surveys in Valles region, southern Bolivia, and the possible role of Valles for the evolution of the Andean avifauna. Rønde, Denmark: DIVA (Technical Report, 1).

Maijer, S. (1996): Distinctive song of highland form maculicollis of the Red-winged Tinamou (Rhynchotus rufescens): evidence for species rank. Auk 113: 695-697.

Mayer, S. (1996): Bird sounds of Bolivia / Sonidos de aves de Bolivia, 1.0. CD-ROM. Bird Songs International, Westernieland, The Netherlands.

Herzog, S. K., Kessler, M., Maijer, S. & Hohnwald, S. (1997): Distributional notes on birds of Andean dry forests in Bolivia. Bull. Brit. Orn. Club 117: 223-235.

Maijer, S. & Fjeldså, J. (1997): Description of a new Cranioleuca spinetail from Bolivia and a "leapfrog pattern" of geographic variation in the genus. Ibis 139: 606-616.

Maijer, S. (1998): Rediscovery of Hylopezus (macularius) auricularis: distinctive song and habitat indicate species rank. Auk 115: 1072-1073.

Maijer, S., Herzog, S. K., Kessler, M., Friggens, M. T. & Fjeldså, J. (1998): A distinctive new subspecies of the Green-cheeked Parakeet (Pyrrhura molinae, Psittacidae) from Bolivia. Orn. Neotrop. 9: 185-191.

Mayer, S. (1999): Bolivian Spinetail Cranioleuca henricae and Masked Antpitta Hylopezus auricularis. Cotinga 11: 71-73.

Mayer, S. (2000): Birds of Bolivia / Aves de Bolivia, 2.0. CD-ROM. Bird Songs International, Westernieland, The Netherlands.

Mayer, S. (2000): Birds observed during a walk from Narvaez (Tarija) to Villa Charcas (Chuquisaca), Bolivia, in March 1992. 27 pages.,%20version%20oct%202000.pdf

Mayer, S. (2010): Birds of Bolivia / Aves de Bolivia, 2.22 DVD-ROM. Bird Songs International, Enschede, The Netherlands.

Mayer, S., Coopmans, P., Krabbe, N., Isler, M. & Cohn-Haft, M. (in prep.): Vocal evidence for species rank to Cercomacra nigrescens fuscicauda Zimmer.