Sex differences in lovebird behaviour
Cocks and hens of the Agapornis species that are most commonly held in captivity - roseicollis,
personatus and fischeri - cannot be distinguished from each other by their appearance.
The sex of a lovebird can only be reliably determined based on breeding results,
endoscopy or DNA research. Many lovebird owners are convinced though, that their behaviour can also
give information about the sex of lovebirds.
Lovebird owners who visit this website participated in a research where we tried to answer the
following question: are there sex differences in lovebird behaviour?
During preparation of the research
(end of 2005) Wessel van der Veen composed a
table that provides an overview of properties
that are mentioned in the literature to distinghuish between the Agapornis sexes.
Many of those properties are related to behaviour. The lovebird owners who participated
in the research filled in an
online questionnaire that asks for possibly sex related
behaviour of their own lovebirds.
Results
General
A total of 73 online forms was filled in by 44 different lovebird owners. Of the 73 forms, three
were excluded. Two because they contained information about more than one lovebird at once, one
because it was a double. Data of 70 birds were available for analysis.
Sex
Based on breeding results and/or research, the sex of 30 lovebirds (43%) was known.
There were 19 hens (27%), 11 cocks (16%), and 40 unknowns (57%). The larger number of hens
is explicable: even when females are not held as part of a breeding couple, they may give evidence for
their sex by laying eggs. Therefore, the unknowns probably consist of more males.
Age and species
The age of the 70 lovebirds varies from 10 weeks to 13 years - 28% is one year old or younger, 52% is
twee years old or younger, 73% is three years old or younger, and only 15% is
older than 5 years. Age is significantly correlated to one of the behaviours:
masturbation is more often reported for older lovebirds. The distribution over species
is as follows: 40 roseicollis (57%), 20 personatus (29%), 7 fischeri (10%) and 3
other (4%).
(advertentie)
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Behaviour and sex
Only data of the 30 lovebirds whose sex is known, are suitable to answer the research question:
are there sex differences in lovebird behaviour?
For testing diferences in behaviour between cocks and hens, only the blue (cock) and pink (hen)
shaded data in the tables below are used. Below each table, the chi squared test value is mentioned.
For tests of 2x2 tables, a continuity correction has been applied. Effects are considered statistically
significant if the p-value is smaller than 0.05. All significant effects were validated by
recalculating the p-value in a Monte Carlo procedure.
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Table 1. Bites when held
| | hen | cock | unknown | total |
| bites at once | 42%
(8) | 9%
(1) | 18%
(7) | 23%
(16) |
| bites in an exploring way | 47%
(9) | 18%
(2) | 40%
(16) | 39%
(27) |
| does not bite | 11%
(2) | 64%
(7) | 33%
(13) | 31%
(22) |
| never held/ don't know | 0%
(0) | 9%
(1) | 10%
(4) | 7%
(5) |
Hens more often bite at once, cocks more often don't bite,
X2[2] = 10.9, p = 0.004.
Table 2. Sitting posture when resting
| | hen | cock | unknown | total |
| distance between feet as broad as shoulders | 84%
(16) | 0%
(0) | 56%
(22) | 55%
(38) |
| distance between feet narrower than shoulders | 16%
(3) | 100%
(11) | 44%
(17) | 45%
(31) |
The distance between the feet is narrower than the shoulders for cocks, for hens it is ofen as broad.
X2[1] = 16.6, p < 0.001.
Table 3. Masturbation
| | hen | cock | unknown | total |
| masturbates by rubbing against object | 32%
(6) | 18%
(2) | 28%
(11) | 27%
(19) |
| masturbation never observed | 68%
(13) | 82%
(9) | 73%
(29) | 73%
(51) |
Both cocks and hens masturbate. The difference is not significant.
X2[1] = 0.138, p = 0.710.
Table 4. Tail signals
| | hen | cock | unknown | total |
| Tail signals, spreading of the tail feathers | 63%
(12) | 27%
(3) | 26%
(10) | 36%
(25) |
| Tail signals never observed | 37%
(7) | 73%
(8) | 74%
(29) | 64%
(44) |
Tail signals are reported for cocks as well as hens. More often for hens, but the difference is not significant.
X2[1] = 2.30, p = 0.130.
Table 5. Feeding
| | hen | cock | unknown | total |
| receives feed most often | 63%
(12) | 0%
(0) | 25%
(10) | 31%
(22) |
| gives feed most often | 11%
(2) | 82%
(9) | 28%
(11) | 31%
(22) |
| alone/ no difference/ don't know | 26%
(5) | 18%
(2) | 48%
(19) | 37%
(26) |
Cocks are clearly more often the feed giving sex.
X2[1] = 12.9, p < 0.001.
Table 6. Bringing materials to the nest
| | hen | cock | unknown | total |
| busy all the time, stressed | 47%
(9) | 9%
(1) | 5%
(2) | 17%
(12) |
| now and then, relaxed | 26%
(5) | 55%
(6) | 13%
(5) | 23%
(16) |
| not at all (while there is a nest) | 5%
(1) | 9%
(1) | 15%
(6) | 12%
(8) |
| never had a nest/ don't know | 21%
(4) | 27%
(3) | 67%
(26) | 48%
(33) |
Hens and cocks often both bring materials to the nest. There is a trend that hens are more often busy all the time,
but this is (just) not significant.
X2[2] = 4.81, p = 0.090.
Table 7. Before intercourse: spreading wings
| | hen | cock | unknown | total |
| spreads wings before intercourse | 68%
(13) | 27%
(3) | 5%
(2) | 26%
(18) |
| does not spread wings before intercourse | 5%
(1) | 36%
(4) | 25%
(10) | 21%
(15) |
| intercourse never observed/ don't know | 26%
(5) | 26%
(4) | 70%
(28) | 37%
(53) |
Cocks as well as hens sometimes spread the wings before intercourse. But hens display the behaviour significantly more often.
X2[1] = 3.97, p = 0.046.
Table 8. Before intercourse: scratch the head
| | hen | cock | unknown | total |
| scratches the head before intercourse | 16%
(3) | 55%
(6) | 30%
(12) | 30%
(21) |
| does not scratch the head before intercourse | 47%
(9) | 9%
(1) | 10%
(4) | 20%
(14) |
| intercourse never observed/ don't know | 37%
(7) | 36%
(4) | 60%
(24) | 50%
(35) |
Cocks as well as hens sometimes scratch their heads before intercourse. But cocks display the behaviour significantly more often.
X2[1] = 4.33, p = 0.037.
Table 9. Breeding
| | hen | cock | unknown | total |
| breeds the eggs | 68%
(13) | 18%
(2) | 0%
(0) | 21%
(15) |
| does not breed the eggs | 21%
(4) | 64%
(7) | 5%
(2) | 19%
(13) |
| never had eggs/ don't know | 11%
(2) | 18%
(2) | 95%
(38) | 60%
(42) |
The literature consistently tells that only hens breed. The two cocks that were reported to breed are therefore unexpected.
Possibly, going into the nest has been taken for breeding? Hens display the behaviour significantly more often.
X2[1] = 5.05, p = 0.025.
Table 10. Feeding the young
| | hen | cock | unknown | total |
| feeds the young | 32%
(6) | 55%
(6) | 0%
(0) | 17%
(12) |
| does not feed the young | 0%
(0) | 9%
(1) | 0%
(0) | 1%
(1) |
| never had young/ don't know | 68%
(13) | 36%
(4) | 100%
(40) | 81%
(57) |
Cocks and hens both feed the young. Just one cock was reported not to feed the young. The difference between cocks and hens is not significant.
X2[1] = 0.00 p = 1.000.
Conclusie
Some behavioural differences between cocks and hens are so large, that they are statistically significant even
at a small sample size (30). The three strongest effects:
* Hens more often bite at once when held
* Cocks are more often feed giving, and hens more often feed receiving partner
* Cocks hold their feet closer together
The sex specific behaviours around intercourse - spreading the wings, scratching the head and feeding -
may be a bit less suitable to use as indicators for lovebirds that are not yet held as a cock-hen couple.
Many lovebirds in this research of which the sex was known, are part of a couple that already successfully
breeded. The literature states that, within a couple of two lovebirds with the same sex, a sort of male-female
roles appear - Dilger, WC (1960). The comparative ethology of the African Parrot Genus
Agapornis. Zeitschrift für Tierpsychologie 17 (6).
The fact that large differences in behaviour between Agapornis cocks and hens exist, has been proven through
statistical testing. Whether those differences are large enough to succesfully compose couples, remains questioned.
The probability that two randomly chosen lovebirds are male and female is 50%. By closely observing behaviour,
this probability can be increased. But if you want to be sure and the lovebirds have not breeded yet, you would
be better off relying on endoscopy or a DNA test.
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Lovebird language
Lovebirds do not learn to speak that easy. But better admit it: do you sometimes talk to your
lovebirds? The below collection may help you improve your communication skills!
(click the button in the left column to hear the sound) |
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| Sound | Interpretation | species |
age | sex |
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"could I have something to eat?" | personatus | 1 day | unknown |
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"I'd like something to eat..." | personatus | 3 weeks | unknown |
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"I want to eat something. Now!" | personatus | 5 weeks | unknown |
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"Release my foot, please!" | personatus | 3 months | hen |
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"let go, that's mine!" | personatus | 1 year | hen |
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"will this be a suitable nest?" | personatus | 1,25 years | hen |
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"I do not agree" | personatus | 1,25 years | hen |
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"hello, is someone there?" | personatus | 1,5 years | cock |
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"Mind me, I'm still here!" | personatus | 1,5 years | cock |
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"please, feed me? alrighty" | personatus | 2 years | cock and hen |
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Some good websites with general information about lovebirds:
* www.agapornis.be/english - a lot of reliable information about lovebirds
* www.parrotparrot.com/lovebirds - an informative and entertaining lovebird website
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