Bird Droppings: Telling Diarrhoea From Polyuria

Quick answer

Most owners who report bird diarrhoea are not looking at diarrhoea. They are looking at polyuria, which is too much clear liquid in an otherwise normal dropping, and the two have different causes and different urgency.

A bird dropping has three separate parts that arrive together: the faeces, the urates, and the urine. Learning to read the three parts separately is the single most useful health skill a bird owner can have, because a bird that hides every other sign of illness cannot hide what lands on the cage paper.

Watching a bird quietly from outside the cage, then reading the paper underneath, tells you more than catching and handling the bird.

• The dark coiled part is faeces. The white or cream part is urates. The clear puddle is urine.
• Diarrhoea means the dark faecal part has lost its shape. Polyuria means the clear part is larger while the faeces stay formed.
• A wet patch on the paper with a normal formed dropping in the middle of it is polyuria, not diarrhoea.
• Green or yellow urates, black tarry faeces, or fresh blood are same-day veterinary problems whatever the consistency.
• Line the cage with white paper, not with substrate that hides the evidence.

Decide in 60 seconds

Why a bird dropping has three parts

Mammals produce urine and faeces separately. Birds do not. The digestive tract, the ureters and the reproductive tract all empty into the cloaca, and everything leaves through one vent at the same moment.

The dark part is faeces from the gut. In a seed-eating bird it is usually dark green to olive brown, and it is extruded as a neat coil or sausage that holds its shape.

The white or off-cream part is urates. Birds convert waste nitrogen into uric acid, which needs very little water to excrete, and that is what a bird carries instead of a bladder full of liquid. Urates should be chalky white or slightly cream, and opaque.

The clear part is true urine, the water fraction. It is normal to have some. How much is normal depends almost entirely on the diet.

That last point is the source of most false alarms. A bird eating fruit, cucumber, or a lot of fresh greens passes far more water than a bird eating dry seed, and the paper looks alarming while the bird is perfectly well.

What a normal dropping looks like

The faecal coil holds a defined shape and does not smear when it lands.

The urate cap is white or cream and sits on or beside the faeces.

The clear ring is present but modest, and the paper dries without a large stain.

The whole thing is roughly consistent through the day. Morning droppings are usually the largest because the bird has been holding overnight.

Colour tracks the food. Pellet-fed birds often produce brown droppings, and coloured pellets can produce startling colours that mean nothing at all. Beetroot, blackberries, cherries and red pepper all pass through and can be mistaken for blood.

The bird itself is half of the assessment. Bright eye, smooth held-in feathers and a normal posture make a dropping change far less worrying than the same change in a fluffed bird.

The most useful habit is to photograph a page of normal droppings from your own bird while it is well. Every bird has its own baseline, and a photograph from a healthy week beats any description in an article.

Polyuria: the change that is usually not an illness

Polyuria is an increase in the clear water fraction with the faeces still formed.

It is the normal response to eating watery food. Fruit, salad, cucumber, melon, sprouted seed and a large bowl of fresh greens all show up on the paper within hours.

Stress and excitement do the same thing. A car journey, a vet visit, a house move, a new person in the room, or a fright will produce a run of watery droppings in a bird that is otherwise fine.

Hens in lay pass very large, wet droppings because they hold them while sitting, and a broody hen's droppings can be several times normal size.

Those causes resolve. Polyuria that continues for days on an unchanged diet does not, and that is when it becomes a medical sign. Persistent polyuria and polydipsia, meaning the bird drinks noticeably more, appear together in kidney disease, diabetes mellitus, liver disease, heavy metal poisoning and chlamydiosis, and none of those improve with waiting.

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A quick way to separate the two at the cage.

Tilt the paper. If a formed dark coil slides across a wet halo, that is polyuria. If the dark part smears into the wet and has no edge of its own, that is diarrhoea.
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True diarrhoea and what lies behind it

Diarrhoea is a loss of form in the faecal component itself. It smears, it has no coil, and it often pastes the feathers around the vent.

Diet is the commonest trigger, and it is usually an abrupt change rather than a bad food: a new brand introduced overnight, a sudden increase in fruit, or spoiled or mouldy food left in a warm cage.

Infection is the next group. Bacterial overgrowth, yeast, avian gastric yeast, giardia and other parasites, and chlamydiosis all produce loose droppings, and several of them are contagious to other birds in the house.

Then there are the causes that are not about the gut at all. Liver disease, heavy metal poisoning from zinc or lead in cage parts and household objects, kidney disease and systemic infection all change droppings. So does a bird that has eaten something toxic.

A bird with unformed droppings that is also quiet, fluffed, or off its food is not having a dietary upset. It is ill, and the droppings are one sign among several.

Colours and what they actually mean

Green or yellow urates.

The white part should never be coloured. Green or yellow staining of the urates comes from bile pigment and points at the liver, or at chlamydiosis, which is transmissible to people. This is a same-day sign even in a bird that looks well.

Lime green, pea green faeces in a bird that is not eating.

A bird that has eaten nothing passes bile-stained green material because there is no food to colour it. Combined with reduced dropping size this means the bird has stopped eating, which is an emergency.

Fresh red blood.

Bright blood on the dropping can come from the cloaca, the lower gut, a cloacal papilloma, or a straining hen. It can also be beetroot. If you have not fed anything red, treat it as blood.

Black tarry faeces.

Digested blood from higher in the tract turns black and sticky. It is a serious sign and is often associated with heavy metal poisoning or ulceration.

Undigested seed in the droppings.

Whole seed passing through means it is not being digested. Proventricular dilatation disease, pancreatic disease and severe gut disease all do this, and it warrants investigation rather than a diet change.

Bubbly or gassy droppings.

Gas in the droppings suggests bacterial fermentation in the gut and is worth a vet visit rather than a wait.

The routine that catches problems early

A gram scale and a written weight are how you tell a bird with a wet cage paper from a bird that is losing ground.

Weight is the tiebreaker. Droppings can look worrying for a day and mean nothing, but weight does not lie. A bird weighed on the same gram scale at the same time each morning gives you a trend, and a falling trend turns a mild dropping change into a same-week appointment.

Line the cage with plain white paper rather than shavings, corn cob, sand or grit. Substrate hides droppings, grows mould underneath, and can be eaten.

Change the paper at a fixed time so you always know how many hours of droppings you are looking at.

Look before you throw it away. Ten seconds a day is enough.

Photograph anything abnormal while it is fresh. Colour changes as it dries, and a photograph on a phone is far more use to a vet than a description.

What never to do

Do not withhold water from a bird with loose droppings. Dehydration is the thing most likely to kill it.

Do not starve a bird for a day to rest the gut. That advice comes from dogs. A small bird that stops eating is in danger within hours.

Do not add vinegar, garlic, tea, or any home remedy to the drinking water. Birds drink less when the water tastes wrong, which is the opposite of what you want.

Do not switch the diet on the day the droppings change. You lose the only information you had, and an abrupt change makes gut upset worse.

Do not clean the vent feathers by pulling at dried crust. Soften with plain warm water on cotton wool and dab. Skin under a soiled vent tears easily.

Do not assume a bird that eats and plays is fine. Birds conceal illness until it is advanced, and the droppings often change first.

When to get help

Same day for coloured urates, black or bloody droppings, unformed faeces in a bird that is also quiet or fluffed, or a sudden drop in the number or size of droppings.

Within the week for polyuria that persists on an unchanged diet, for a bird drinking noticeably more, or for undigested seed passing through.

Immediately, out of hours, for a bird sitting on the cage floor, breathing with effort, or with a tail that bobs at rest, whatever the droppings look like.

The target is a bright bird with formed droppings, white urates and a stable weight on the scale.

Take the cage paper with you, along with the photographs, the weight record, a list of everything the bird has eaten including treats and anything it chewed, and the age of the bird. A vet can gram stain droppings, test for chlamydiosis, radiograph for metal, and run bloods, and the history decides which of those comes first.