Pallid Scops Owl

An ancient Elb Tree Ziziphus spina-cristi stands proudly in the middle of a deep, flat-bottomed wadi in northern Oman. Several thick trunks radiate at angles from its thick, gnarled base, their coarse bark easy to climb. Halfway up one of them, a rounded stone nestles in a fork, a reminder of the occasional flash floods that leave little else behind. Higher still, Egyptian Fruit-eating Bats Rousettus aegyptiacus flap to and fro, plucking small yellow fruits from the broad, undulating crown. 

A Pallid Scops Owl Otus brucei in a neighbouring tree hoots with metronomic regularity. CD2-37 is as loud as he gets, barely enough for a faint aura of collective echoes. For eight nights this male led me on a little tour of his section of the wadi. Each time I managed to work out which tree he was in, I chose it as the site for the next night’s recordings. He had about 40 in his territory and unluckily for me, during those eight nights he never hooted in the same tree twice. This was as close as I got.

A month later I was back, this time with Arnoud. I decided to try my luck in a narrower section of the wadi with only a handful of trees about 800 m to the north. Glowing through a saffron veil of desert dust, the full moon betrayed leaf-toed geckos Asaccus even before they darted away across huge round boulders. 

After several hours of reverie but no point blank recording, I noticed a vague dent in the side of the moon: an eclipse had started. I walked back to ask how Arnoud was faring and have a bite to eat. As I arrived at the old territory the usual pair called from an old Elb that I had tried at least once previously. After they moved on, I approached with the thought of once again placing my equipment high in that tree. It was then that I noticed the LED lights of Arnoud’s recorder. He had chosen this tree for his very first attempt, and must have just made a fantastic recording! René later taught me a funny Dutch word to give vent to my frustration, which would have come in handy on this occasion. Krijgdeovermaassehazewindhonden- korenmolenpestpokke! So here is how a hooting Pallid Scops sounds at a distance of just a few metres, gradually building up steam while silhouetted against a partially eclipsed full moon (CD2-38).

The hooting begins almost inaudibly, a peculiarity of Pallid Scops Owl. Gradually over a couple of minutes it becomes louder and slightly higher-pitched. This male’s 65.6 hoots/minute is almost identical to the 65.5 of one month previously. His nearest neighbour was equally consistent at around 90 hoots/minute. In CD2-39, Arnoud recorded both hooting together. 

Hearing two Pallid Scops Owls duetting like this, apparently close together with one faster and slightly higher-pitched than the other, it is easy to imagine a pair. I had been determined to find out whether this was true. In fact all but a few of these apparent ‘duets’ concern neighbouring males, just as in CD2-39. Females do occasionally hoot, but only briefly. Before giving any examples, however, I would like to illustrate the female’s commonest call, which is quite different.

Female Pallid Scops Owls have a soliciting call directly equivalent to the twiu of Eurasian Scops Owl. In Pallid, however, hooting and  soliciting are easy to tell apart, creating the illusion that the female Pallid solicit more frequently. Sometimes their soliciting calls sound harsh (CD2-40), and at other times the timbre is smooth (CD2-41). At first I thought these were different call types, until I noticed that smooth turns to harsh as soon as the dominant frequency goes above about 650 Hz. Now I hear them as gradations of the same call. By May harsher variants are uncommon, so perhaps they are more aggressive and no longer required after the partners have become more familiar with one another. Over 50 of our 213 recordings of Pallid Scops Owl contain female soliciting calls, but we have only one example from a male (CD2-42).

During the night of 12 April 1982, a party of Swiss birders heard Stock Dove Columba oenas-like calls while camping on the shores of the Euphrates in south-eastern Turkey. The next morning they discovered a pair of Pallid Scops Owls (Hüni 1982). A year later, other Pallid Scops were found in a tea park just south of the centre of the nearby town of Birecık. They were easy to see in the artificial lighting, and seemed hardly to be bothered by the loud music and crowds of people. Within a couple of years the owls became a strong additional incentive, besides the famous colony of Northern Bald Ibis Geronticus eremita, for birders to visit the area. The trick was to order a cup of tea and only then inquire about the whereabouts of the owls. At this, a waiter would happily lead the way to a roosting owl or a nest.

On 3-5 May 1987, Arnoud and about 100 other visitors to the tea park could see the owls well as they preyed on beetles and other insects. They even hunted underneath people’s chairs. Their hooting was almost inaudible even at distances below 10 m (van den Berg et al 1988). In May 2001, I visited Birecık too.

In  CD2-43, a tea park female gives three smooth soliciting calls, then two hoots that morph into a series of faster and slightly harsher soliciting calls. At the same time a male, probably her mate, hoots at a lower pitch in the background. A few minutes later the female hooted a longer sequence, but the recording was spoiled by traffic.

In Oman, we gradually amassed further evidence for female hooting. In May 2013, Arnoud made three recordings where both members of our favourite pair hooted together. In each case, the female hooted for brief periods before reverting to her usual soliciting calls, while the male hooted for much longer periods. CD2-44 starts with the male hooting. The female joins in with a single soliciting call, gives four hoots, and then reverts to soliciting. Hooting of this particular female was only slightly higher-pitched than her mate’s, with maximum frequency between 400 and 520 Hz. Another female reached a maximum of just under 650 Hz. 

Most Pallid Scops Owl sounds are remarkably low-pitched, but males have a very high-pitched copulation call similar to that of Eurasian Scops Owls. CD2-45 starts with a soliciting call of a female. Her mate starts hooting, and gradually she becomes more excited. The male’s copulation call comes towards the end.

A quiet, dove-like rukutu may be Pallid Scops Owl’s equivalent to the croaking call of Eurasian Scops Owl. CD2-46 starts with three soliciting calls of a female, and then we heard the male’s rukutu. Every now and then one of the owls preens vigorously enough to shake the small branch supporting the microphones. On another occasion, Arnoud recorded calls that seemed to morph from normal male hoots into this rukutu sound.

Pallid Scops Owl’s excitement calls have an arched shape like those of the other three Western Palearctic Otus owls. Pallid is the lowest (CD2-47), and Eurasian is the highest-pitched in both call-types. 

Breeding takes place about a month earlier than in Eurasian Scops Owl, with a peak from mid to late April in Arabia (Jennings 2010), and probably no later than the first week of May in Turkey (van den Berg et al 1988). Pallid Scops Owl is highly nocturnal although in April 2010, René and I heard one hooting in broad daylight. In Oman, where Pallid Scops is resident, the main period of hooting starts in January (Sargeant et al 2008), and we have found May to be a peak month. In mid-July, Arnoud heard no calls at all.

Juvenile Pallid Scops Owls have begging calls very similar to those of Eurasian Scops Owls, just slightly lower-pitched. In late May 2014, I found three broods in Oman by listening for their very short, frequently repeated hissing calls. In CD2-48, up to four fledglings are begging in a small tree right above the microphones. I first detected these calls from a distance of at least 75 m. 

In southern Israel, Pallid Scops Owl is a migrant and winter visitor. During a study of their ecology and distribution over two winters, Lerman et al (2006) located 24 individual owls, all of which were roosting in acacias located in desert washes in the Arava valley. James Smith, one of the authors of the study, told me: “I never once heard a wintering Pallid Scops Owl call in southern Israel. I did try to hear vocals on several occasions, making sure that I was close to known roosting birds at dusk and even tried playback couple of times. The birds appear to be silent whilst wintering, at least during my experiences with them (annual from 1997 through to current date). I’ve never heard mention of other observers hearing them either…” The only winter sound that has ever been described is bill-clicking in the hand (Mundkur 1986). 

I never found a Pallid Scops Owl during the day, and have rarely seen them even at night. Once I was lying on a flat rock under a full moon, listening and drifting close to the threshold of sleep. My equipment was doing the hard work under an Umbrella Thorn up on the opposite slope, where I hoped that an owl would hoot. About 2 m away from me was a small bush, and suddenly something fell from it, maybe a large leaf or a twig. I looked round, but in the moonlight I could see nothing untoward. A couple of minutes later some flapping quickened my senses. I felt something touching my forehead and looked up to see a Pallid Scops Owl fluttering right over my face for a moment, before flying off to the nearest tree. I sometimes wonder if I dreamed this.

When Sclater coined the word ‘Palæarctic’ in 1858, he included Africa north of the Atlas, Europe, Asia Minor, Persia and Asia north of the Himalayas, northern China, Japan and the Aleutian Islands. Palaios is a Greek word meaning ‘old’, referring to the Old World, and arktikós means ‘northern’ or literally, ‘of the bear’. The Ural River is a convenient and universally accepted border between the Eastern and Western Paleartic in the north. A southern border is more difficult to define. 

Popular opinion, based mainly on ‘BWP’ (Cramp 1985), includes most of the Sahara in but only the northernmost part of Arabia. As we worked on Undiscovered owls, we began to question why southern Arabia had been excluded. Roselaar’s (2006) well reasoned definition of the Palearctic includes most of the peninsula. To keep things simple we went a step further and included the whole of Arabia. This added three more species to the book, including one final scops owl that was brought to light by a spy.

>>> Arabian Scops Owl  Otus pamelae >>>