Life Giving Water

Water quality is a good predictor of human health. When the water is good, life is good and when the water is bad, you get sick people and sick environment.

Intact forests  play an important role to ensure that ensures there is fresh, clean water for both wildlife and human beings. But deforestation disrupts the water cycle.

The removal of trees results in the groundwater tables getting depleted because the trees lose their function of helping the soil absorb flowing water. The land then becomes unproductive as soil properties responsible for supplying soil nutrients are leached from rain falling freely on the soil. The large quantity of sediments washed away from deforested areas end up in streams and river cause high turbidity and siltation, causing negative  impacts on fisheries further downstream as far as the reefs.

The surest way to ensure a good water supply is to keep forests intact.

water necklace

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Birds and their coloured feathers

The colours observed in bird feathers is made up of keratin, carotenoids, and melanin or a combination of the three.

feather Keratin serves a structural function in the construction of feathers. The keratin differs in implantation, thickness and stiffness of the rachis and barbs, symmetry and curvature of vanes. This structural design plays an important role when the bird combines colour and pattern to produces different signals.

Carotenoids are the pigments responsible for most bright reds, oranges, and yellows. Carotenoid cannot be synthesized by animals, and must be included in the diet, and are often limited in nature. Colours and ornaments that rely on carotenoids are costly to produce. Carotenoid is ingested from the diet at the time the bird is moulting and the colour gets deposited in the feathers.

Melanin pigments are deposited as black or dark brown granules within the epidermal cells. They create colour effects in combination with other pigments. Melanin adds strength and abrasion-resistance to keratins. Melanin is also a predictor of dominance, hormonal balance, foraging abilities, and provides protection from ectoparasites.

The gene responsible for melanin has been identified down to a single locus. This gene is highly variable for different birds and produce a colour ranging from the black, grey, brown to reddish brown and the yellow in chicken chicks.

The persistence of colour variations  in birds from generation to generation shows that feather colour is an inherited trait. Apart from the genetics, the amount of light variation in the environment also controls the variation observed in bird feather colour.

The amount of light in the environment is affected by the environmental features, for example, a forest with trees would exaggerate shadows when contrasted to a treeless environment. Furthermore, the light spectrum changes with increasing altitude.

Bird plumage can be classified into three groups according to the reflecting properties of the light as would be seen by the birds. Type A feathers have strong reflecting properties while type B has no reflective properties; and Type A/B only gives a weak reflection. Melanin colours ranging from pale yellow, chestnut, and brown and, black does not reflect much light in the ultra-violet (UV) range.

 The patterns observed on feathers are created by the scattering of light by ordered layers of melanin granules within the keratin of the barbs. The birds are capable of either repeating exactly from one set of feathers to the next or varying to produce apparent differences between sexes, age group and populations.

The green colour in parrots and other green birds is rarely acquired through the diet, but is a combination of yellow and blue. If the yellow is a Type A then the reflectance will be high, but if the yellow contains melanin then the green will result in Type A/B. CSC_0828

The red coloured feather is most times type A/B.  The type A/B red is mostly observed in birds that inhabit areas with more precipitation where red radiation is weak and allows the bird to blend into a dark background making the bird less conspicuous in the dense canopy of the rainforest.

Many bird species that are involved in predator-prey relationships exhibit colour polymorphism. These birds tend to move continuously, have a generalist habitat requirement and a widespread but patchy distribution. The Owl is a good example.

The adaptative function of melanin type B plumage on the cuckoo brood parasites is related to its life style of stealth.  The dull plumage has no reflectance and therefore is cryptic and conceals the presence of the parasitic bird near host nests. Furthermore, the arrangement of the bars on the feather which is arranged in the broken fashion enables the bird to remain cryptic in the undergrowth of the woodlands and mangrove bush while it searches for possible host.

The Bird of Paradise feathers seem to be the attraction for mate choice. A male with bright colour signals good nutritional condition and could be related to his ability to forage for the high quality food. As a result, bright colours in the male bird have been associated with the ability to provision, disease resistance, dominance and the honest advertisement of sexual prowess. The extra feathers on the Bird of Paradise does not have any aerodynamic significance but developed as a result of selection by females. The choosy female achieves the highest fitness by mating with an individual displaying the feature that signals the best quality.  However such trait often impairs foraging success and increases predation risk, so that only high quality individuals can afford such a trait and only high quality males are chosen by the female.

When human beings begin to understand the importance of feather color to birds, we shall begin to see the implication of our actions of selectively harvesting beautiful feathered birds, or removing bird habitat through logging. Or even the detrimental effects of keeping bids in aviaries as an excuse for conservation.

Forgive us our sins against the birds

cassowary_3Birds have been in the center of human attention since the dawn of time. The birds have inspired human cultures – from adornment, to dance moves, to habits. Birds as food is well-documented in human historical archives. Birds have even found a place in religion – immortalized in songs, stories, and rituals. Bird figurines are fashioned from precious stones, carved into wood, shaped out of a rock, molded into glass and even beaten onto metal. Some models are miniature replicas, others like the Nazca  hummingbird outline in the Peruvian desert is close to 100 meters in length and can only be seen from the air.  The modern technological feat of air travel has its source of inspiration in birds.

Once upon a time, beautiful and exotic bird feathers had their price weighed in gold and were traded alongside spice and precious metals. From high couture to indigenous culture, bird feathers has been and is still being used as a significant dress accessory.

Apart from satisfying human values, birds also serve important ecological function. Birds carry pollen from flower to flower ensuring seed production.  The birds even disperse seeds across the landscape that eventually grows into trees in the forest.

Selective harvesting of the best looking bird to satisfy human desire has caused certain bird populations to decline. Through natural selection over time, the brightest bird with the handsomest feather is also the possessor of good genes. Selectively removing the best birds removes the good gene from the gene pool.

With anti-pouching laws in place, extinction through harvest had been minimized. The main threat on birds these days is anthropogenic activities that destroy the habitat of the bird. Logging is one such destructive activity. Logging obliterates the home of the birds and destroys their food source, and in turn paves the way for increased predation.

Climate change, an anthropogenic driven change to the world climate is driving birds up the altitude and when there is no more space, the birds go over the edge. Extinction is inevitable. When that will happen is just a question of time.

Locking birds in aviaries is not a substitute for preservation. If animal indeed do have rights, then keeping birds in aviaries is a crime.   Birds are born to soar into the heavens but aviaries clip the wings of these birds and subdue their instinctive need for depth and breadth in space.  Studies have identified that most tropical bird species are nomads or transient species and move within  certain latitudinal gradients over a large area following availability of food.

In a mixed flock aviary, a number of birds are put into a single aviary. In the wild, these birds would not normally associate. In nature some of these birds occupy space at the top of the canopy while others in the mid canopy and others in the understorey. This division is a function of adaptation to minimize competition. At the different levels, the micro-climate is also specific for the insect, fruits and small plants found in that layer – which in turn is food for the birds. An aviary does not take that into consideration.

Birds in aviaries are fed a standard diet of fruits. Even if all are frugivores, some species feed on insects for extra nutrients. Others have been seen in the wild to practice geophagy – or soil eating for its mineral and salt content. The feathers of birds serve special function including advertisement of fitness, health, sexual fitness, camouflage and even stealth. Colored features are not grown but are the result of ingesting the colors from the food that is eaten.  Being fed a standard diet compromises the integrity of fitness advertisement.

Some birds need to remain in a group for competition to ensure the fittest genes are selected. For instance, the lek in Bird of Paradise is done by a group of male birds and never done by individual birds. Furthermore, without the required environment, a bower-bird may not be able to build required dance area to entice the female.

Just like humans, a reduction in personal space results in different psychological issues. Aggression, depression are two main ones. But changes can happen at the cellular level that affects other functions like mating rituals, reproduction and even the responsibility of rearing chicks.

At the end of the day, when humans finally meet the maker of the birds, we will be found guilty of all the bad things we have done against the birds.

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