The Greater Vasa Hen’s Breeding Behavior in Captive Scenarios
The
purpose of this entry is to answer one question apropos of the coracopsis v.
v. hen’s reproductive modalities that underpins a larger picture about her
character, activities, habits, and feedings.
I sketch a picture that compares and collocates all three Greater Vasa
species, i.e., c. vasa, c. comorensis, and c. drouhardi. In the first section I emphasize the
distinction between instinct and character staged within a constructed debate
between Aristotle and Darwin. In the second, I identify a problem in the
received opinion about the Vasa hen’s breeding behavior. In the third, I resolve the problem in the
second.
The
Greater Vasas are the largest of the African and Asian parrots, twenty inches
long, and they are often said to resemble Australian parrots more than any
other African species. Hence, when we talk about physical characteristics, the
Vasa does not fit well with the other African parrots that one can group easily
together (e.g., African greys, Jardines, poicephalus). The only shared
characteristic they have with African pscittacines are behavioral or
dispositional. This becomes difficult since we have only had them in the United
States from the 1970s.[1]
They, along with the Madagascar and red-faced
lovebirds, both belonging to the genus agapornis, display sexual
dimorphism. Concepts like ‘sexual
dimorphism’ seem hard to classify historically however much they are of
importance for our account of Vasa hen reproductive behavior.[2] .JPG) |
| A fifteen week old Vasa chick by Marc Morrone, Parrots of the World, Rockville Center, NY |
I. Darwin and Aristotle on ‘instinct’ and ‘character’
A Philosophical & Historical Framework for Vasa Reproductive Behavior
In his History of Animals[3] Aristotle focuses on his thought that the biological capacities for food and reproduction constitute what unites all animals under a common genus in light of their status as necessary conditions for a mature animal’s active life.[4] From the assumption that an animal’s life activities can be divided into two acts (i.e., reproducing and eating), and within the context of this framework pivoted on procreation and feeding, Aristotle seeks out which activities are relevant to each animal by dint of what most essentially is at stake for animals in terms of how much of their activity concentrates on this two-part necessary interest. I assume that Aristotle believes that their activities are mostly constituted by their character or disposition. Aristotle infers an animal’s ‘character’ from its observable behavioral modes. How much of these behavioral modes are instinctual? How could we know, and with certainty, which, out of the plurality of theories on character disposition, could be the criteria for providing a materially adequate answer to this question? And if we were interested in applying this question to a specific organism, namely, the Greater Vasa parrot, how, within this Aristotelian framework, would we proceed?
In
Charles Darwin’s account of natural selection in his The Origin of Species
he gleams with an idea that follows in Aristotle’s course of reasoning however
much Aristotle’s thought is premature for Darwinian ‘instinct’. Darwin
considers some conditions and criteria for attributing ‘instinct’ to
animals. I suggest that Darwin’s
exploration here provides a foil to Aristotle’s view of animal character.
Darwin’s “Instinct”
Darwin
emphasizes ‘instinct’ in animal behavior, in the eighth chapter titled
‘Instinct,’ by foregrounding the importance of ‘character’ in an instinctual
state so that character does play a role in how populations survive over time.
A population’s survival is, Darwin often reminds, constrained by environmental
factors that modify and fix desirable features, that is, features, or elements,
of the organism’s constitution that are responsive to change where change is
suffered to benefit the species so that the species may thrive in futurity.
How
does any of this Darwinian instinct concern Aristotle’s question? Aristotle’s
syllogistic form of reasoning to an end may seem to be programmed into an
organism’s identity. For human beings we
never chose to have the capacity to reason yet we can reason and thus actualize
this capacity proper to our species. The
practical syllogism in this light may seem to constrain our heredity. This constraint, one might further argue, is
like an instinct insofar as we, just in virtue of our rational cognitive
capacities, persist by way of reasoning toward a goal. However, 'instinct' suggests for the
contemporary reader and for readers of Darwin's era unconscious forces -
Aristotle did not have the conceptual apparata for anything unconscious. These
forces, Darwin insists, influence our deliberations in a way that Aristotle's
picture of syllogistic practical reasoning forecloses. The whole point of introducing a syllogistic
model for human action is, for Aristotle, to suggest an actively thinking
intellect that is not subject to any passive force whatsoever. Since instincts suggest automatic expression,
and Aristotle thinks that reasoning cannot arise haphazardly so as to come
about without deliberation, he cannot hold instinct in his concept of animal
character
Since
I am pressed to fix the discussion about a specific organism, namely, the Vasa,
I can only sketch out some preliminary thoughts, from anecdotal information, on
why certain behaviors, proper to the Vasa’s characteristic disposition, appear
in this pscittacine’s taxon. We need, and which is what Aristotle
provides at HA VIII, a psychological account of animals to distinguish
the Vasa’s activities from her characteristic life form given our sketched out
framework apropos of how animals as such develop habits as such and how they
feed on what they do as a result.
Drawing from his experience as a
biologist, Aristotle illustrates the elusive and central concept of character
by suggesting that “certain traces of psychical qualities or attitudes” are
observed not only in ourselves but in other animals similar to ourselves. Such psychical qualities are natural
capacities exercised by some mental apparatus. Agreeing with Aristotle's point
that animals' "habits and modes of living ... vary according to their
character and their food" (HA VIII.i.588A1ff), I will expound upon
the Vasa parrot first by sketching out her animal character and her dietary
needs; from here we can infer the Vasa's habits and life modalities and imagine
how they fall in with her physical appearance. Aristotle’s thought is, as noted
above, premature for Darwinian ‘instinct’, which considers some conditions and
criteria that the earlier thinker could not have thought up, however much
Darwin’s exploration provides a foil to Aristotle’s animal character. In any case, the captive Vasa hen’s
reproductive activity, her copulation and subsequent brooding, shows an answer
to a more theoretical, comparatively historical, philosophical question when we
ask whether it is necessary for her to behave as she would in the wild, as a
polyandrous, promiscuous creature.
Since
I am asking about the necessity between the Vasa hen’s reproductive behavior
among suitors and her chicks’ futurity and fitness, ‘instinct’ is of conceptual
importance. Is her polyandrous
reproductive mode instinctual? I.e., do
they arise from unconscious forces within her?
And are her vocalizations to her male counterpart(s) necessary (or
necessarily instinctual) in both captivity and in the wild? These questions extend beyond what I can say
- simply because parrot behavior, whether in the wild or in our homes, whether
in a flighted aviary or in a single cage, is beyond overdetermined and far
beyond our current understanding of parrot ethiology, ecology, sensory and
perceptual and cognitive processes, et relata for the simple folk
psychology of ‘unconscious forces’. Activities are mostly constituted by an
animal’s character or disposition, character inferred from observed behavioral
modes - at least for our Aristotle. When
the Vasa hen calls out in high pitch to a nearby favored suitor for food,[5]
and we hear these same vocalizations each day and feel a connection between
them and her food supply, we include the vocalization patterns within our
concept of the Vasa hen’s disposition and behavioral capacities or range.
Physical Changes Supervenient on Reproductive Behavioral Modalities
Although
physical changes (e.g., pigmentation) do not fall within either character disposition
(i.e., the whole set of activities, including habits, abilities, capacities) or
life activities (e.g., eating, reproducing) and life patterns (e.g., flight
patterns, patterns of vocalizations) or even habits (e.g., burying her chicks
under nest box materials[6]),
the hen’s reproductive dispositional mode inheres in important physical
characteristics within the breeding season[7]
- about which we are inquiring.
In
the beginning of her reproductive cycle, her activity coincides with marked
changes in her plumage, beak, and skin coloration. Her variety of hues contains elements of blue
in sunlight. More often, during the non-breeding season, she appears dark
brown. She also appears grey. Either the brown or the grey appearance
depends on which perspective the spectator views her, since she has more than
sixty shades of grey and dark brown. When she is not breeding and out of
season, her undertail-coverts stand gray and black streaks accompany them. Her non-breeding primary remiges are also
gray up to their outer edge. Unlike the c. v. drouhardi, a subspecies of
the more general taxonomic genus, though both subspecies integrate in the
eastern region of Madagascar, with the c. v.v.’s distribution moreso to
the western segment, the c. v. v. has a slightly different coloration in
her undertail coverts. The c. v. drouhardi has non-coverts that are
grayish white, a lighter plumage than our hen has.[8] When she is ready to breed, her head feathers
disintegrate and she is left bald or with patches of baldness. Her skin color soon becomes a saffron mustard
yellow, a taxicab yellow - just imagine orange-yellow skin for your otherwise
pasty pale skinned parrot![9]
Her ceres and eye rings are naked and grey notwithstanding. During the breeding season the beaks of both
the male and female c. v. vasa become one-third wider.
As for habits in captivity Vasa parrots do not appear to be
one person birds nor do they seem to have problems with other Vasas. Vasas are naturally gregarious and this is
evidenced by their flocking behaviors in the wild. Vasas tend to flock in congregations of three
to eight. Vasas tend to roost in
communities and ornithologists report sightings of hundreds of birds in a
single large tree. There are some advantages to considering a Vasa parrot over
other parrots of its size. Unlike for most other parrots of the Vasa parrot’s
size, Vasas do not seem to develop common psittacine behavioral problems
(e.g., feather plucking, screaming).[10] Vasas also produce
considerably less dust and dander than do cockatoos and African greys. When
kept as companion pets, the c. v. vasa has an affectionate affinity for
its caretakers in a way similar to a cockatoo.[11]
The
vocalizations of the c. v. vasa include whining and “peek-a-boo” like
intonations. Steve Garvin, proprietor of
The Feather Tree, suggests that the Vasa parrot’s “natural voice is like a
grouse or a donkey.” Both Vasa subspecies whistle in song in a way comparable
to whistlings of the wild Cape parrot and African grey.[12] Foster observes that the Vasa’s utterances do
not reach the volume of an Amazon’s though the volume does topple that of a
cockatiel. In addition, if an apartment dweller takes interest in the Vasa
parrot for its lower volume range, one, Foster suggested to me, should assess
by whom one’s apartment is flanked. If
one’s neighbors cannot tolerate noise, then one might want to consider a
quieter avian companion. Vasas, like
most other African parrot species, can mimic sounds from their environment
(e.g., microwaves, phones) - another shared behavioral character among
Africans. Vasas do not ululate in shrill
pitch frequently but, when they do, it usually is a sign that they are nervous
or afraid of some perceived object within their immediate surroundings. Vasas
whistle in this way when either perched or in flight.[13]
These vocalizations have a pitch higher during the three to four months
surrounding the spring breeding season and it is usually the hen’s shrill cries
rather than the cock’s, relates Garvin.
II. The Received Opinion about “Necessity” for Vasa Hen Promiscuity
Our
hen, drab and ashen in her crow like semblance, with her long wings and
non-graduated tail, her pronounced cere, is remarkable for her polyandrous
reproductive modality in her homeland Madagascar. But what about in aviculture, in breeding
programs? Celebrated accounts on the
Vasa never fail to mention just how she needs, i.e., she could not have it
otherwise, multiple cocks for her brood’s fitness and futurity. These pundits do not seem to support what
they have not argued for yet but assume - the relation, causal, as received
opinion takes as dictum, between the hen’s demands from the plurality of
suitors and her chicks’ fitness (past rearing and fledging, weeks one through
six). Her vocalizations, social behavior
during and outside the breeding season, her antics before and while in heat,
and her notorious breeding paradigm at home pushes many to consider her
requirements for breeding in aviculture to match those in the wild. If the goal in writing on Vasas is earmarked
to equip the prospective investor, conservationist, breeder of the Greater Vasa
- an important goal since deforestation of the sliver of land on the inlet
proper to Madagascar’s Comoro Islands continues to prevail and the Vasas in
captivity decrease exponentially (thanks partly to the global economic crisis),
then this aim does not materialize properly and the aviculturist goal does not
(and has not) come across with the success it sought to attain. The Greater Vasa is also listed under CITES
II as endangered - another sign that aviculturists should help reduce pressures
on wild populations and part of doing this comes from thoroughly understanding
how to get captive Vasas breeding (and why it is that they breed via the
constructed and chosen paradigms). The
prospective Vasa husbandry enthusiast should at least have a minimalist picture
of how the parrot can breed and carry on its species in both captivity and the
wild. If the Vasa needs three males to
feed her nest chock full of neonates, then writers should emphasize this in
their exhortations on how to set up the breeding paradigm. In what follows I
cannot paint the entire picture of this paradigm. Instead, I only have room to show what the
received opinion has been and how to clarify its shape. Why does it seem necessary to many writers on
the Greater Vasa female's practice of neonatal care that she rely on her song -
or what some call a loud shrill bleak cry, a demand for food for her babies
from whichever male will serve her, she does not discriminate - to attract
multiple males to aid her chickadees’ rapidly increasing crops and developing
metabolizing structures.
In
his observations in “Greater Vasa Parrot Breeding Survey”, Blynne suggests that
a polyandrous “cage grouping, with the extra males, … shows promise for the
future” (58).[14]
His account, as Marc Morrone pointed out to me, is not scientific and this
observation of his should not mislead the prospective breeder of Vasas to setup
each hen with more than one male. A Vasa
hen in captivity does not need more than one male simply because a hen in the
wild does in the case of both copulation and roosting. Blynn also suggests that
development and fertility depend on the polyandrous behavior of the hen - “...
[i]nfertile eggs in earlier years added extra males and they now produce
yearly.” So, fertility somehow correlates with multiple males per hen. “One greater female, two greater males and
one lesser all placed in one cage in ’90.
Produced the first year.” This
does not mean, however, that adding more hens will yield this result each time.
III. Resolution - Polyandry in Captivity Need Not Be, However Possible, for The Six Weeks
Captive
situations differ from wild ones in the case of food and feeding her very large
chicks. More males are not necessary in captive situations, relates Morrone and
Koloupos, because food and protection are abundant. Multiple suitors are not
needed to insure the supply of food – human caretakers are. Desborough told me that, in the wild, extra
males likely provide food because one male will not be able to find
enough. After all, males must forage,
which means travel a distance; so, finding just enough that will hold in his
crop is a grave challenge, he must concentrate all his efforts and energies on
this, as Aristotle said earlier, vital, if not most important, life
activity. If a hen has three or four
babies in her nest, her suitors must
find quite a bit per feeding - and she demands that these suitors fill her
babies’ crops. And these cocks can be
sure that they will have multiple feedings within that short six weeks (i.e.,
from hatching to fledging) since the chicks grow therein. So, how much the male must work and how many
males per hen depends on the hen’s clutch size.
And that is the answer to this present investigation.
IV. Conclusion
So, is it necessary (or not) in captivity that the Vasa hen
rely on her song to attract multiple male Vasas, if she even needs multiple
males? “Females with higher song rates attracted more males, and as a result
received significantly more food,” reports Ekrstrom.[15] Does the addition of
more than one male determine her brood's weaning and fledging (i.e., come the
six weeks)? My exploration with several
vasa breeders and the primary and secondary literature has convinced me that
there is no necessity here, not forthe hen’s reproductive behavior – whether
copulation or roosting – to involve either polyandry or promiscuity in
captivity. (Do note that Ekstrom studied
wild populations of Vasas in western Madagascar, not Vasas in breeding programs
for the sake of raising pet quality Vasas or Vasas within our palpable domain.)
So, there is no necessity for polyandrous behavior to determine a successful
outcome come the six weeks - at least not in captivity. Does this mean that it might not work out
for some scenarios? Of course not. Monica Vallair, who works for Texas breeder
Lou Roberts, has her breeding Vasas set up one hen to two males. We also cannot forget about Blynn’s success
in 1990. On the other hand, some scenarios
work against this. Koloupos found aggression from Vasa hens when adding
additional males. In any case, my
investigation into whether the Vasa hen needs one suitor for feeding and
reproducing brings Aristotle’s inference not only to light but also down from
the abstract world of philosophos to the very material and enchanting world of
aviculture.
ᙬᙩ
Special thanks to Longo’s Aviaries,
Milkwood Aviaries, Marc Morrone, Daniel Koloupos, Stephany Klein, Monica
Vallair, Steve Garvin, and Laurella Desborough for insightful comments and
support.
Works Cited
W.S. (1927). "Bangs on a New
Parrot from Madagascar" in The Auk. 44 (2) 278-9
Doane, Bonnie Munro. (1991). The
Parrot in Helath and Illness: An Owner’s Guide. New York: Howell Book
House.
Dowsett, R. J.; Forbes-Watson, A. D.
1993. Checklist of birds of the Afrotropical and Malagasy regions.
Tauraco Press, Li.
Ekstrom, J.M, Burke, T.T.,
Randrianaiana, Le.L. & Birkhead, T.R. (2007). “Unusual Sex Roles in a
Highly Promiscuous Parrot: The Greater Vasa Parrot Coracopsis vasa” in The
International Journal of Avian Science, 149(2), pp. 313-20.
Forshaw, J.M. (1989). Parrots of
the world. Princeton: Princeton University Press.
Juniper, T and M. Parr. (1998). A
Guide to Parrots of the World. New Haven: Yale University Press.
Langrand, O. and I. Sinclair.
(2003). Birds of the Indian Ocean Islands: Madagascar, Mauritius, Réunion,
Rodrigues, Seychelles and the Comoros. Cape Town: Struik.
Moustaki, N. (2003). A New
Owner's Guide to Lovebirds. Neptune City: T.F.H. Publications.
Peters, W.K.H. (1854) - Ngazidja
(Grand Comoro), Mwali (Moheli) and Ndzuani (Anjouan) in Comoros.
R. Thorstrom and R. T. Watson
(1997). “Avian inventory and key species of the Masoala Peninsula, Madagascar”.
Bird Conservation International,7, pp 99-115.
[1] Tracing the origins of Vasa
importations proves tricky. Morrone
tells me that he first saw them in Canada back in 1980. The internet grapevine has Connecticut
breeder Timothee Grazee as the first importer of this parrot, but this is
speculative.
[2] Related concepts that are also tough can be seen in
Ekstrom’s essay on Vasa promiscuity: “We describe sexual dimorphism, sexual
promiscuity, copulation behaviour, parentage (using molecular markers) and the
unusual singing behaviour of females, and discuss these different features to
provide an overview of the Greater Vasa Parrot’s extraordinary mating system.”
[3] Hereafter ‘HA’.
[4] Cf. Arist. De An. II.iv.415A20ff
[5] Desborough remarks that her Vasa does not have “favored
suitors” when she gives her cry for her nestlings’ food - “she doesn’t say,
‘hey, Jim, feed my babies’, and later ‘hey, Ed, my babies need to eat’, she
does not, in other words, discriminate between males; she just cries out a
blanket cry that is specific for feeding her chicks, not, on top of that, for
particular suitors to feed her.”
Ekstrom’s paper, however, suggests that the more successful hens, at
least in the wild, display higher song rates, which may, although Ekstrom does
not show this in his paper, involve tailoring songs to specific males.
Successful hens, in Ekstrom’s study, were those with larger clutches and with
better overall health; as a result of how much higher their song rates were,
these hens were fed better by males.
[6] See Bono, Lisa. A. “African Parrots - Unique Behaviors of African Parrots” in Bird
Talk November 2011, p. 25: “Female
vasa parrots tend to bury eggs and even chicks while they nest. This is often a behavior reserved for
reptiles and not seen in other species of parrots.”
[7] It is important to note that the breeding season is the
spring usually around May to June. However, the pairs begin in a somewhat
‘instinctual’ way to prepare for this productive stretch of time as early as
January. Mate selection, Desborough
informs, does not begin until April (earliest).
The season tapers off by August, completed by September (latest).
[8]Juniper, p. 146 (plate 63).
[9] Ekstrom’s observations of this sexual dimorphism in wild
Vasas reveal the hen’s “taxicab mustard yellow” bald head period to be
restricted to the chick-rearing weeks, not the later fledging weeks (p. 315).
He compares the differences between the non-orange headed male Vasa with the
female to show the dimorphism (316).
[10] Morrone insists, however, that the possibility of a plucker
is a permanent one in captivity - “even pigeons and chickens pluck in
captivity,” he urges.
[11] Interestingly, the Vasa parrot and the cockatoo - alongside
the Keas - are born with hard beaks. See
Kawaldie https://sites.google.com/site/kawaldie/breedingbehavior.
[12] Forbes-Watson, pp. 114-115.
[13] Juniper, p. 146.
[15] p. 317
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