THE BROWN TIT (Mamma morena)
IntroductionThe Brown Tit Mamma morena belongs to the family Mammidae and is one of four widely distributed species of which this is particularly prevalent in the tropical and subtropical regions. The other three species are the numerous Oriental Tit M. orientalis, the Dark or Chocolate Tit M. nigra which appears to be in regression in many parts of its natural habitat, and the scarce Indigenous Tit M. ignobilis which is either totally ignored or persecuted, especially in its range in the Americas and the relict South African, Australian and New Zealand populations. Although all have bred interspecifically, at times producing some interesting specimens, in general they have all maintained their specific identity. It is with the Brown Tit that this paper is concerned although reference will be made to the other two species. Evidence will be given of demographic increase, the races and morphs to be found and the correlation of these with climatic condition throughout the range of the species, as well as discussing the various and varied morphs.
Historical
The Brown Tit was first described in detail in a series of written communications, none of which are quotable, towards the end of the 19th century by the Reverend Augustus Sludgeworthy, B.D., sometime vicar of the deservedly inundated village of Peeling Bogmarsh. Sludgeworthy commented upon his observations to a small but like-minded group of observers in southern and eastern England and in particular to one George 'One-eye' Midgely who was for many years a privileged guest of H.M. Prison Service as he had been sentenced to a long term of penal servitude as a result of attempting to carry out in situ nocturnal observations of the species at the home of the Hon. Mrs. Willington-Smythe in South Kensington, something which was regarded as extreme folly by those who knew the lady in question, the custodial sentence imposed coming soon after his release after several weeks in Charing Cross Hospital.
In those far-off days, the species was exceedingly rare and more often than not the specimens observed were considered to be albinistic or at the very least leucistic. They were also considered to be separate species by some and more than one observer referred to them as the Pallid or Glaucous Tit M. alba. More recent observations along the shores of the Mediterranean and southern and western North America have shown that this is a purely transitory phase caused by lack of ultra violet light (u/v), as will be shown later.
Research in those days was limited by the confines of the meteorology in southern England as well as by the lack of optical instruments suitable for long range observation of a species which then was known for its exceptionally shy and retiring nature. It is interesting to note that in the past thirty years there has been a radical change in the behaviour and this will be considered briefly.
The tenacity with which Sludgeworthy and his small band of fellow enthusiasts carried out their work is all the more praiseworthy, especially in view of the objections raised by the very subjects of thier study and the exceedingly dim view with which the judicial system regarded their activities. Suffice to recount one of these tales to show the difficulties which this ardent band of watchers, or voyeurs as they were then known, met.
The incident in question took place on the shingle of the Chesil Beach in the county of Dorsetshire during the course of the Whitsuntide Bank Holiday of 1897. The Rev. Sludgeworthy, having espied what he took to be an example of the albinistic form of the species some way along the beach and which was occasionally showing itself from behind a large, yellowish boulder, decided to stalk it with the aim of carrying out a series of close range observations aided by his binoculars with a magnification of 2.5, the aforementioned boulder concealing him from view.
Boldly ignoring the gaze of the occasional stroller and the bothering attentions of a depraved Golden Retriever, he stalked the occasional tantalising flashes of white along the shingle until, by his calculations, the specimen in question could only be a few yards away on the other side of the yellowish boulder. Raising himself inch by inch, he was able to catch fleeting glimpses of the rara avis until, ever vigilant as it was in those days, it uttered its sharp alarm call.
One can well imagine the amazement of Sludgeworthy when the large boulder (on which he was resting his elbows with the natural reaction of steadying his fieldglasses because of the shaking of his nerves in the excitement of the moment) suddenly came to life beneath him. He had been, in fact, resting his elbows on the recumbent form of a sumo wrestler from the Land of the Rising Sun who was touring England with an aim of popularising that sport. Sludgeworthy may indeed be forgiven for thinking, as he expressed himself later to the judge after he had come out of hospital, that a miniature but particularly violent earthquake was taking place beneath him. The vision of the large oriental gentleman pursuing Sludgeworthy along the Chesil Beach conjures up unforgettable images.
Neither the physical damage to which he was subjected, nor a term in the local prison, nor the comments made by the judge about 'a man of the cloth' appear to have dampened his ardour for such esoteric research and it was shortly after this that he commenced his correspondence with 'One-eye' Midgely. It was entirely due to the very christian efforts of Sludgeworthy that, in the course of his long confinement during Her Majesty's pleasure, Midgeley was able to metaphorically keep abreast of current developments in research, although he often lamented the absence of the possibilities of ‘hands-on’ fieldwork in his replies.
It was not long after Midgeley's release that they collaborated on a paper which was presented at a reunion held at the summer residence of the Count of Foudre-les-Deux near Cap Ferrat in which they suggested the creation of the subspecies Mamma morena alba. This subspecies is now regarded as being the one to which the majority of specimens of England and northern Europe belong. On this trip they were both able to observe at close range specimens which closely resembled descriptions given from the type locality and were privileged to take biometric measurements of a captive specimen maintained by the Count himself, although it was apparently given to fits of hysteria when observed by strangers.
Sludgeworthy was also one the observers, along with some 200 more and thus proving that twitching is not a modern phenomenon, of the first British record of M. nigra on 24th December 1908 at the Finchley Music Hall. Sludgeworthy was, like the rest of the observers, overcome by excitement and failed to take the detailed notes. By the standards of modern ornithological requirements for a modern rarities committee there would have been doubt about the record but corroborative evidence was given by the heir to the Duchy of Cornwall and his accompanying party from the Brigade of Guards.
Until the early 1960s little more work of a scientific nature was done in northern Europe, most observers being unsuitably qualified amateur practictioners and certainly its distribution was little known. It was thought to be patchy at the very least and certainly related to climatic conditions although there was, and still is, a certain aberrance in its southern Scandinavian and north German origin. Since then much more work has been carried out on its populations and their distribution.
Evidence for population increase.
As noted above, the species was certainly rare throughout northern Europe until at least the middle of the 20th century and there is some scanty evidence that the same could be said for southern Europe also. This scarcity is attributed to the social mores as well as correlating with a lack of affluence and lack of suitable air travel.
However, since the mid 1950s and early 60s and coincident with the last two factors noted above, much work has been done on the distribution of the species and its populations, an expansion most visible on the northern shores of the Mediterranean Sea, although absent on the southern shores of that sea and in all countries of the Moslem faith (eg: Khomeini, A., 1980). Concurrent with the population increase has been a change in the habits of the species with a massive reduction in its timidity and where once shy and retiring it now positively flaunts itself (eg: Penthouse, 1965 et seq.; Playboy, 1961, et seq.).
The massive explosion of northern Mediterreanean populations, comprised in large part by the sporadic migratory habits of examples of northern European origin, seems to have occurred as a result of sudden social affluence and acceptance of the change in social liberty which has continued to the present and looks like continuing. There has been no such massive change in southern and western regions of North America and this appears to be governed by puritanical factors and it is still very often restricted to very localised areas with few inhabitants and an ample supply of sand dunes. Conversely, in South America and, notably, in Brazil it is often seen and the greatest affluence coincides with the carnival time where it is often observed in brilliant, if not scanty, partial plumages.
Subspecies and dominance
Taxonomically the existence of the superspecies M. morena remains open to discussion according to some authors. There seems to be little doubt that the original stock came from Africa as long as four million years ago and from which the other species developed (eg. Leakey et al., various publications), which means that M. nigra must have taxonomic priority, although in itself it was almost certainly a descendent of ignobilis. Actual development of M. morena appears to have taken place in Europe several tens of thousands of years ago, possibly as much as 750.000 years, and with subsequent migrations into northern Europe. M. occidentalis originated from ignobilis stock when some of the population migrated from eastern Asia into North and then South America in the last 25.000 years. There have also been small, localised migrations of orientalis in to the Americas in the past 150 years. Migration of morena into the same areas in the past 500 years and enforced migration of nigra took place in the period between 1600 and 1800.
The major irruptive waves of M. morena into Africa in the past 500 hundred years resulted in a struggle for dominance with the endemic M. nigra and it is only in the past 40 years that morena has lost its apparent dominance and nigra itself seems to be intent on wiping itself out.
The superiority of M. morena in the Americas has continued in most areas although demographic increase of nigra in the north has gone some way towards palliating the former dominance of morena. Former theories of specific dominance in both Europe and North America as proposed by A. Hitler in 1925 in Mein Kampf and by the KKK in North America are still to be found.
With exception of ignobilis, which is only just holding its own or generally declining in many areas of its range, there is ample evidence of the demographic increase of the remaining three species. In the case of orientalis there has been extreme fecundity which has resulted in population saturation in many parts of its range (eg. Japan, China and India) with the resultant habitat degradation. Evolution of nigra has had similar degrading environments results in many parts of its habitat although ultimately disease and genocidal tendencies are also reducing its population in several areas (eg. Somalia, Sudan and Ruanda). In the case of morena, demographic increase in Europe is stagnating and it has been postulated that this is favouring great demographic expansion of nigra in the years to come, as in many areas morena is showing a tendency to depend upon such input, although not necessarily favouring its full specific integration.
Races or morphs?
It has been suggested by several observers, largely as a result of field observations rather than by detailed biometric data and the handling of the species in the field, that there should be at least three races of Mamma, as indeed there are of the other species: maxima, media and minor. However, it has been shown that these morphological features are unstable from one generation to the next and that classification is impossible in juvenile females unless one wishes to emulate 'One-eye' Midgely, and it is not until the species is in virtually adult plumage that such assignation be effectively carried out. Even when adult, all races are highly vociferous and invariably reject and attempt at serious biometric measurement on a quantitative basis by casual observers, all of which factors pose grave problems, especially in the satisfactory determination of subspecific status where the case is borderline. It is, therefore, better to regard all the four species as polymorphic with regard to size.
The suggestion of subspecific status for the forms flaccidus and erectus is not regarded as valid. These are, in any case, preceded taxonomically by the same names in Homo sapiens, the former being a substitute for nointeressans and the second for excitans and this, in particular, is purely temporal on a very short-term basis. It is perhaps better to treat all of these as polymorphic variations, just as it is with undoubted colour morphs such as alba, ruber and pallidus.
However, it is still possible to arrive at some overall, although somewhat generalised, conclusions as to the classification and distribution of the species morena and nigra and the morphs of these from fieldwork in Europe and North America, as well as occasional casual evidence of vagrant orientalis, these mostly of Japanese origin, in both of those regions.
In the case of morena, the spread of the forms maxima, media and minor seems to be fairly evenly spread across the population, with regional preponderances of the first two on beaches in California, Florida and parts of the Mediterranean. In the case of nigra, there are big differences, the most well known being the so-called 'mammy' phase of monumental proportions, often shown in old Hollywood films (eg. 'Gone with Wind', 1939), which is still to be found in parts of the southern USA and Caribbean. However, this seldom extends to the native African population where wide scale malnutrition makes this morph somewhat difficult to encounter except on a very localised basis in specimens at the very top of hierachal scale. It is interesting to speculate what might happen should the nutritional availability change, which seems most unlikely on the basis of current evidence. The species orientalis appears to vary between media and minor, maxima being extremely rare and and virtually unknown in Europe, its natural shyness making field encounters difficult.
The concurrence of the morphs alba and ruber appears to occur only in morena as far as is known, the presence of these being present in orientalis is still under investigation. The morph alba is nothing more than a leucistic or even albinistic form of morena. Detailed research along the shore of the northern Mediterranean has conclusively shown that, when subject to prolonged exposure to ultraviolet light, irrruptive members from northern Europe show a transient period, more or less prolonged, of the morph ruber. The colouration of this phase varies between a pale pink and bright scarlet before finally attaining the brown shades of a typical morena. Such u/v exposed specimens often exhibit a strong dermal moult. It is interesting to note that endemic Iberian specimens show less evidence of the ruber morph and rapidly move through this to the morena morph.
Temporal distribution
There is, in virtually all cases, a strong correlation between the 25ºC isotherm and distribution, although certain Nordic specimens have been observed at lesser temperatures. Studies along northern Mediterranean shores show that as the ambiental air temperature increases, so does the number of specimens in any given area of sandy shore. Along the southern Mediterranean shore this species is never observed as all potential records have been strongly suppressed by the religious authorities, these being encouraged in some regions by the use of lapidation.
There is always a strong winter loss of colour from September or early October onwards, although there are occasional winter specimens to be seen without any loss of the morena plumage. These may be found in sheltered sites when the weather is fine and sunny and wind protection is available but with the increasing awareness of skin cancer possibilities, there appear to be fewer of these in recent years (unless they have already succumbed).
The first spring records usually occur on fine, sunny days from late March onwards with the appearance of the first alba and occasional ruber morphs. although this is usually regained rapidly in spring from March or April onwards in the case of Iberian specimens, these often reaching full morena status by late May or early June in the case of the more advanced specimens, and this lasts until as late as October in many cases.
More detailed study shows a much greater incidence in favoured areas from mid May onwards. Maximum abundance occurs from mid June and especially between mid July and the end of August. This abundance is coincident with localised Iberian irruptive movements and also longer range ones from northern Europe to the Mediterranean coasts. During this period, large quantities of all morphs in their many combinations may be easily observed without the aid of optical apparatus at very close range from mid morning onwards (sunrise plus 4 hours) until sunset.
Numbers decline quantitatively during September and by the end of that month there are fewer to be seen. Remaining specimens are often geriatric examples, often in a state of advanced decay. Selective culling of these geriatric specimens as a deterrent and with the aim of keeping a healthy and attractive breeding stock has often been suggested but authorities are quick to decline such ideas.
Warning The use of optical apparatus in the flocking areas should be undertaken with care, as irate mates have been known to be extremely aggressive. In such case, long range work should take place.
Conclusion
The elevation of the morphs maxima, media and minor to subspecific label is not recommended. This is seen as a folly and a sop to 'splitters', most of whom must also be 'twitchers' without the necessary stamina to carry out prolonged fieldwork, tied as they are to their car steering wheels or other forms of transport.
Until such time as future research shows it feasible, observers will have to be content with seeing the species Brown Tit Mamma morena with, for example, morphs media and ruber visible in the same specimen. Splitting serves only to confuse the issue, which is the continued enjoyment of field observation by all watchers until they go blind or insane. It is strongly recommended that intensive fieldwork be carried out in order to closely monitor future trends.
Warning The use of optical apparatus in the flocking areas should be undertaken with care, as irate mates have been known to be extremely aggressive. In such case, long range work should take place.
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