Welcome to the Bird Chromosome Database (BCD)
The BCD is an open resource that comprises information about chromosome number, karyotype, and the advances obtained by Fluorescent in situ Hybridization (FISH) studies in birds. The main purpose of this database is to retrieve and organize historical/current information regarding avian cytogenetics. Furthermore, it also aims to stimulate the development of new studies in this field.
Analysis of the data available in V6.0/2025
The new version (V7.0/2026) of the BCD includes chromosome number data for 1,214 bird species (1,100 with published karyotypes and 262 with chromosome-level genome assemblies), as well as chromosome painting data using Gallus gallus (GGA) probes for 135 species.
| Infraclass | Order | Total number species* | Number of species karyotyped | % | Genome in chromosome level | % | Number of species with WCP data | % |
| Paleognathae | ||||||||
| Struthioniformes | 2 | 1 | 50.0% | 1 | 50.0% | 1 | 50.0% | |
| Casuariiformes | 4 | 2 | 50.0% | 1 | 25.0% | 2 | 50.0% | |
| Apterygiformes | 5 | 1 | 20.0% | 1 | 20.0% | 0 | 0.0% | |
| Rheiformes | 2 | 2 | 100.0% | 1 | 50.0% | 2 | 100.0% | |
| Tinamiformes | 46 | 6 | 13.0% | 1 | 2.2% | 1 | 2.2% | |
| Galloanseres | ||||||||
| Anseriformes | 178 | 48 | 27.0% | 34 | 19.1% | 10 | 5.6% | |
| Galliformes | 307 | 56 | 18.2% | 12 | 3.9% | 16 | 5.2% | |
| Neoaves | ||||||||
| Phoenicopteriformes | 6 | 3 | 50.0% | 1 | 16.7% | 0 | 0.0% | |
| Podicipediformes | 22 | 4 | 18.2% | 1 | 4.5% | 0 | 0.0% | |
| Mesitornithiformes | 3 | 0 | 0.0% | 0 | 0.0% | 0 | 0.0% | |
| Pterocliformes | 16 | 1 | 6.3% | 1 | 6.3% | 0 | 0.0% | |
| Columbiformes | 352 | 32 | 9.1% | 7 | 2.0% | 11 | 3.1% | |
| Musophagiformes | 23 | 3 | 13.0% | 1 | 4.3% | 0 | 0.0% | |
| Otidiformes | 26 | 2 | 7.7% | 2 | 7.7% | 0 | 0.0% | |
| Cuculiformes | 157 | 12 | 7.6% | 2 | 1.3% | 3 | 1.9% | |
| Opisthocomiformes | 1 | 1 | 100.0% | 1 | 100.0% | 1 | 100.0% | |
| Gruiformes | 190 | 30 | 15.8% | 6 | 3.2% | 5 | 2.6% | |
| Charadriiformes | 394 | 67 | 17.0% | 17 | 4.3% | 6 | 1.5% | |
| Caprimulgiformes | 98 | 8 | 8.2% | 1 | 1.0% | 0 | 0.0% | |
| Podargiformes | 16 | 1 | 6.3% | 1 | 6.3% | 0 | 0.0% | |
| Steatornithiformes | 1 | 0 | 0.0% | 1 | 100.0% | 0 | 0.0% | |
| Nyctibiiformes | 7 | 1 | 14.3% | 1 | 14.3% | 0 | 0.0% | |
| Aegotheliformes | 10 | 0 | 0.0% | 1 | 10.0% | 0 | 0.0% | |
| Apodiformes | 478 | 14 | 2.9% | 8 | 1.7% | 3 | 0.6% | |
| Phaethontiformes | 3 | 0 | 0.0% | 1 | 33.3% | 0 | 0.0% | |
| Eurypygiformes | 2 | 2 | 100.0% | 1 | 50.0% | 1 | 50.0% | |
| Gaviiformes | 5 | 1 | 20.0% | 1 | 20.0% | 0 | 0.0% | |
| Sphenisciformes | 19 | 8 | 42.1% | 3 | 15.8% | 0 | 0.0% | |
| Procellariiformes | 149 | 5 | 3.4% | 2 | 1.3% | 0 | 0.0% | |
| Ciconiiformes | 20 | 14 | 70.0% | 3 | 15.0% | 3 | 15.0% | |
| Suliformes | 54 | 11 | 20.4% | 3 | 5.6% | 0 | 0.0% | |
| Pelecaniformes | 120 | 35 | 29.2% | 8 | 6.7% | 6 | 5.0% | |
| Strigiformes | 256 | 32 | 12.5% | 4 | 1.6% | 3 | 1.2% | |
| Accipitriformes | 263 | 68 | 25.9% | 13 | 4.9% | 12 | 4.6% | |
| Coliiformes | 6 | 1 | 16.7% | 1 | 16.7% | 0 | 0.0% | |
| Leptosomiformes | 1 | 0 | 0.0% | 0 | 0.0% | 0 | 0.0% | |
| Trogoniformes | 47 | 2 | 4.3% | 1 | 2.1% | 1 | 2.1% | |
| Bucerotiformes | 75 | 6 | 8.0% | 2 | 2.7% | 0 | 0.0% | |
| Coraciiformes | 185 | 13 | 7.0% | 1 | 0.5% | 0 | 0.0% | |
| Piciformes | 444 | 34 | 7.7% | 5 | 1.1% | 2 | 0.5% | |
| Cariamiformes | 2 | 2 | 100.0% | 0 | 0.0% | 0 | 0.0% | |
| Falconiformes | 65 | 14 | 21.5% | 7 | 10.8% | 6 | 9.2% | |
| Psittaciformes | 409 | 83 | 20.3% | 10 | 2.4% | 10 | 2.4% | |
| Passeriformes | 6758 | 474 | 7.0% | 93 | 1.4% | 30 | 0.4% | |
| Total entries | 11227.00 | 1100 | 9.8% | 262 | 2.3% | 135 | 1.2% |
Frequency of diploid number in birds
The database will be updated regularly and all users are encouraged to contribute to the improvement and spreading of bird cytogenetic information.