Natural History and Classification

 

Owls have existed on earth for a tremendously long amount of time. They have adapted to nearly every type of environment from the heat of the desert to the cold of the tundra.  In research project using DNA performed in 1985, Sibley and Ahlquist proposed that owls began to diverge from other nocturnal predators around 70-80 million years ago (Johnsgard, 2002).  The closest related birds are the nightjars, which are of the order Caprimulgiformes. The similarities between these two orders include the arrangement of their feather patterns and the structure of their vocal organs (Johnsgard, 2002).  Unlike the majority of owls, nightjars spend most of their time on the ground (Farrand, 1994).  The owl developed to pounce on its prey and kill it quickly, so it evolved the talons and beak to make that type of hunting most efficient.  The advantage of capturing prey during times of low light is most likely the reason why they developed strong sight during the nighttime (Johnsgard, 2002). 

 

The evolution of the modern owl resulted in two distinct lines, the Strigidae family and the Tytonidae family. Through fossil records, the Tytonidae family appears to have differentiated first.  Fossil evidence was found and dated to be from the Eocene Period, while the first evidence of the Strigidae family is from the early Miocene times (Johnsgard, 2002).  There have also been fossils of intermediate species found that share characteristics of both families.

 

There are 208 known species of owl in the world: 191 of the Strigidae family and 17 of the Tytonidae family. The only species of the family Tytonidae that occurs in North American is the Barn Owl (Farrand, 1994).  The owls of the Tytonidae family have several characteristics that separate them from the rest of the owls in the Strigidae family. They have heart-shaped facial disks and tend to have longer legs with a comb-like middle toe, called pectinated.  They weave their heads back and forth in a hypnotic motion to scare away attackers, and they also do not make the `hoot’ sound that many people identify with the owl (Owlpages, 2004).



Strigidae (Typical Owls)

191 Species


Aegolius acadicus   Northern Saw-whet Owl

Aegolius funereus    Boreal Owl

Aegolius harrisii      Buff-fronted Owl

Aegolius ridgwayi   Unspotted Saw-whet Owl

Asio abyssinicus     African Long-eared Owl

Asio capensis          Marsh Owl

Asio flammeus         Short-eared Owl

Asio madagascariensis  Madagascar Long-eared Owl

Asio otus              Northern Long-eared Owl

Asio stygius          Stygian Owl

Athene blewitti      Forest Owlet

Athene brama        Spotted Owlet

Athene cunicularia   Burrowing Owl

Athene noctua          Little Owl

Bubo africanus         Spotted Eagle-Owl

Bubo ascalaphus      Pharaoh Eagle-Owl

Bubo bengalensis     Rock Eagle-Owl

Bubo bubo               Eurasian Eagle-Owl

Bubo capensis         Cape Eagle-Owl

Bubo cinerascens    Greyish Eagle-Owl

Bubo coromandus    Dusky Eagle-Owl

Bubo lacteus          Verreaux’s Eagle-Owl

Bubo leucostictus       Akun Eagle-Owl

Bubo magellanicus     Magellanic Horned Owl

Bubo nipalensis          Spot-bellied Eagle-Owl

Bubo philippensis       Philippine Eagle-Owl

Bubo poensis              Fraser’s Eagle-Owl

Bubo shelleyi              Shelley’s Eagle-Owl

Bubo sumatranus        Barred Eagle-Owl

Bubo virginianus        Great Horned Owl

Bubo vosseleri             Usambara Eagle-Owl

Ciccaba albitarsis       Rufous-banded Owl

Ciccaba huhula           Black-banded Owl

Ciccaba nigrolineata  Black-and-white Owl

Ciccaba virgata          Mottled Owl

Glaucidium albertinum     Albertine Owlet

Glaucidium bolivianum    Yungas Pygmy-Owl

Glaucidium brasilianum   Ferruginous Pygmy-Owl

Glaucidium brodiei           Collared Owlet

Glaucidium californicum   Northern Pygmy-Owl

Glaucidium capense           African Barred Owlet

Glaucidium castaneum       Chestnut Owlet

Glaucidium castanonotum  Chestnut-backed Owlet

Glaucidium castanopterum  Javan Owlet

Glaucidium cobanense     Guatemalan Pygmy-Owl

Glaucidium costaricanum Costa Rican Pygmy-Owl

Glaucidium cuculoides    Asian Barred Owlet

Glaucidium gnoma          Mountain Pygmy-Owl

Glaucidium griseiceps   Central American Pygmy-Owl

Glaucidium hardyi            Amazonian Pygmy-Owl

Glaucidium hoskinsii        Cape Pygmy-Owl

Glaucidium jardinii          Andean Pygmy-Owl

Glaucidium minutissimum     Least Pygmy-Owl

Glaucidium nanum            Austral Pygmy-Owl

Glaucidium nubicola       Cloud-forest Pygmy-Owl

Glaucidium palmarum    Colima Pygmy-Owl

Glaucidium parkeri         Subtropical Pygmy-Owl

Glaucidium passerinum   Eurasian Pygmy-Owl

Glaucidium perlatum        Pearl-spotted Owlet

Glaucidium peruanum      Peruvian Pygmy-Owl

Glaucidium radiatum        Jungle Owlet

Glaucidium sanchezi        Tamaulipas Pygmy-Owl

Glaucidium siju                Cuban Pygmy-Owl

Glaucidium sjostedti         Sjostedt’s Owlet

Glaucidium tephronotum  Red-chested Owlet

Glaucidium tucumanum    Tucuman Pygmy-Owl

Gymnoglaux lawrencii      Cuban Screech-Owl

Jubula lettii                        Maned Owl

Ketupa blakistoni              Blakiston’s Fish-Owl

Ketupa flavipes             Tawny Fish-Owl

Ketupa ketupu               Buffy Fish-Owl

Ketupa zeylonensis        Brown Fish-Owl

Lophostrix cristata        Crested Owl

Micrathene whitneyi      Elf Owl

Mimizuku gurneyi          Mindanao Eagle-Owl

Nesasio solomonensis    Fearful Owl

Ninox affinis          Andaman Hawk-Owl

Ninox boobook      Southern Boobook

Ninox connivens    Barking Owl

Ninox ios               Cinnabar Hawk-Owl

Ninox jacquinoti    Solomon Hawk-Owl

Ninox meeki           Manus Hawk-Owl

Ninox natalis          Christmas Island Hawk-Owl

Ninox novaeseelandiae          Morepork

Ninox ochracea          Ochre-bellied Hawk-Owl

Ninox odiosa              New Britain Hawk-Owl

Ninox philippensis      Philippine Hawk-Owl

Ninox punctulata       Speckled Hawk-Owl

Ninox rudolfi             Sumba Boobook

Ninox rufa                 Rufous Owl

Ninox scutulata         Brown Hawk-Owl

Ninox squamipila      Moluccan Hawk-Owl

Ninox strenua            Powerful Owl

Ninox superciliaris    White-browed Owl

Ninox theomacha       Jungle Hawk-Owl

Ninox variegata         Bismarck Hawk-Owl

Nyctea scandiaca      Snowy Owl

Otus albogularis     White-throated Screech-Owl

Otus alfredi             Flores Scops-Owl

Otus alius               Nicobar Scops-Owl

Otus angelinae       Javan Scops-Owl

Otus asio                Eastern Screech-Owl

Otus atricapillus    Variable Screech-Owl

Otus bakkamoena    Indian Scops-Owl

Otus balli                Andaman Scops-Owl

Otus barbarus         Bearded Screech-Owl

Otus beccarii          Biak Scops-Owl

Otus brookii           Rajah Scops-Owl

Otus brucei            Pallid Scops-Owl

Otus capnodes       Anjouan Scops-Owl

Otus choliba          Tropical Screech-Owl

Otus clarkii            Bare-shanked Screech-Owl

Otus collari            Sangihe Scops-Owl

Otus colombianus  Colombian Screech-Owl

Otus cooperi          Pacific Screech-Owl

Otus elegans          Ryukyu Scops-Owl

Otus enganensis    Enggano Scops-Owl

Otus flammeolus    Flammulated Owl

Otus fuliginosus     Palawan Scops-Owl

Otus guatemalae    Guatemalan Screech-Owl

Otus hartlaubi        Sao Tome Scops-Owl

Otus hoyi                Hoy’s Screech-Owl

Otus icterorhynchus       Sandy Scops-Owl

Otus ingens              Rufescent Screech-Owl

Otus insularis          Seychelles Scops-Owl

Otus ireneae            Sokoke Scops-Owl

Otus kennicottii        Western Screech-Owl

Otus koepckeae        Koepcke’s Screech-Owl

Otus lempiji              Sunda Scops-Owl

Otus lettia                Collared Scops-Owl

Otus longicornis       Luzon Scops-Owl

Otus madagascariensis    Torotoroka Scops-Owl

Otus magicus            Moluccan Scops-Owl

Otus manadensis       Sulawesi Scops-Owl

Otus mantananensis   Mantanani Scops-Owl

Otus marshalli           Cloud-forest Screech-Owl

Otus mayottensis        Mayotte Scops-Owl

Otus megalotis            Philippine Scops-Owl

Otus mentawi              Mentawai Scops-Owl

Otus mindorensis        Mindoro Scops-Owl

Otus mirus                  Mindanao Scops-Owl

Otus moheliensis         Moheli Scops-Owl

Otus nudipes               Puerto Rican Screech-Owl

Otus pauliani              Comoro Scops-Owl

Otus pembaensis          Pemba Scops-Owl

Otus petersoni             Cinnamon Screech-Owl

Otus roboratus            West Peruvian Screech-Owl

Otus rufescens              Reddish Scops-Owl

Otus rutilus                  Malagasy Scops-Owl

Otus sagittatus              White-fronted Scops-Owl

Otus sanctaecatarinae   Long-tufted Screech-Owl

Otus scops                     European Scops-Owl

Otus seductus                Balsas Screech-Owl

Otus semitorques           Japanese Scops-Owl

Otus senegalensis          African Scops-Owl

Otus silvicola                 Wallace’s Scops-Owl

Otus spilocephalus         Mountain Scops-Owl

Otus sunia               Oriental Scops-Owl

Otus trichopsis        Whiskered Screech-Owl

Otus umbra             Simeulue Scops-Owl

Otus vermiculatus    Vermiculated Screech-Owl

Otus watsonii           Tawny-bellied Screech-Owl 

Pseudoscops clamator       Striped Owl

Pseudoscops grammicus    Jamaican Owl

Ptilopsis granti         Southern White-faced Owl

Ptilopsis leucotis       Northern White-faced Owl

Pulsatrix koeniswaldiana   Tawny-browed Owl

Pulsatrix melanota              Band-bellied Owl

Pulsatrix perspicillata         Spectacled Owl

Pyrroglaux podarginus        Palau Owl

Scotopelia bouvieri     Vermiculated Fishing-Owl

Scotopelia peli             Pel’s Fishing-Owl

Scotopelia ussheri        Rufous Fishing-Owl

Strix aluco                Tawny Owl

Strix butleri               Hume’s Owl

Strix chacoensis     Chaco Owl

Strix davidi                  Pere David’s Owl

Strix fulvescens           Fulvous Owl

Strix hylophila             Rusty-barred Owl

Strix leptogrammica    Brown Wood-Owl

Strix nebulosa              Great Grey Owl

Strix occidentalis         Spotted Owl

Strix ocellata                Mottled Wood-Owl

Strix rufipes            Rufous-legged Owl

Strix seloputo          Spotted Wood-Owl

Strix uralensis         Ural Owl

Strix varia               Barred Owl

Strix woodfordii      African Wood-Owl

Surnia ulula             Northern Hawk Owl

Uroglaux dimorpha         Papuan Hawk-Owl

Xenoglaux loweryi          Long-whiskered Owlet


 

 

 


Tytonidae (Barn-Owls)

16 Species

Phodilus badius           Oriental Bay-Owl

Phodilus prigoginei     Congo Bay-Owl

Tyto alba              Barn Owl 

Tyto aurantia               New Britain Masked-Owl

Tyto capensis               African Grass-Owl

Tyto deroestorffi               Andaman Masked Owl, Andaman Barn Owl

Tyto glaucops              Ashy-faced Owl

Tyto inexspectata        Minahassa Owl

Tyto longimembris       Australasian Grass-Owl

Tyto manusi                 Manus Owl

Tyto multipunctata      Lesser Sooty-Owl

Tyto nigrobrunnea       Taliabu Owl

Tyto novaehollandiae  Australian Masked-Owl

Tyto rosenbergii          Sulawesi Owl

Tyto sororcula             Lesser Masked-Owl

Tyto soumagnei           Madagascar Red Owl

Tyto tenebricosa          Greater Sooty-Owl