Quick Answer
Most bird species do not intentionally remove feces from their nests. However, some behaviors like eating feces or moving around in the nest can incidentally remove some waste. Birds have evolved to tolerate more unsanitary conditions than humans. Still, excessive feces can increase nestling mortality and lead some bird parents to abandon nests.
Do Bird Parents Purposefully Remove Poop?
Most birds do not make any effort to keep their nests clean by removing feces. However, some birds have adapted behaviors that may incidentally remove some waste:
Eating Feces
Some birds eat the fecal sacs or feces of their young. This serves to keep the nest clean and hide signs from predators, but is not primarily for hygiene.
Moving Nestlings
Parent birds may move nestlings around in the nest, which can move feces to the edges. However, they do not purposely clean the nest this way.
Abandoning Soiled Nests
Birds abandon nests more often when they become excessively soiled. While not removing poop, this prevents continued use of unsanitary nests.
Not All Feces Stays in Nest
Some feces gets flung out of the nest by nestling movements and adult exits/arrivals. However, parent birds do not try to deliberately remove poop this way.
Overall, most evidence indicates birds do not purposefully remove waste from their nests. Poop removal is either incidental or achieved by abandoning soiled nest sites.
Do Bird Nests Stay Clean Naturally?
Bird nests get soiled with feces naturally as nestlings defecate in them. How much waste accumulates depends on several factors:
Nestling Age
Very young nestlings produce small amounts of liquid feces. Older nestlings produce larger amounts of more solid feces.
Nest Placement
Ground nests may get covered in nestling feces over time. Tree nests allow some feces to fall away naturally. Cavity nests concentrate feces.
Nest Materials
Porous nest materials like grasses absorb liquid feces while smooth nest cups allow feces to be pushed over the edge.
Parent Behaviors
As mentioned, some birds may incidentally remove some waste by eating feces or moving nestlings around.
Weather Conditions
Rainfall can wash away nestling feces in outdoor open nests. Sunlight and dry conditions may dry out and crust over liquid feces.
So while birds don’t purposefully keep nests clean, some waste may be removed or minimized naturally. Still, feces do accumulate in active nests.
Do Birds Mind Messy Nests?
Surprisingly, parent birds generally seem to tolerate pretty messy nesting conditions:
Evolved Tolerance
Evolutionarily, birds adapted to raise young in natural cavities and branches that likely had feces, fungi, parasites etc. Their tolerance for “dirty” conditions developed naturally.
Focus on Feeding
Bird parents are primarily focused on frequent feeding of nestlings. As long as nestlings survive, minor unclean factors are irrelevant.
Marshal Nestlings, Not Nests
Bird parents direct their energy towards guarding, brooding and feeding nestlings. Actively managing nest cleanliness is likely not an instictive priority.
Abandon Unsanitary Nests
Birds will abandon nests that become too poopy or parasite-ridden. But their threshold appears higher than human standards.
So nest hygiene does not appear important to adult birds. They tolerate messy nests to a degree as long as the young survive.
Do Dirty Nests Harm Nestlings?
Although parent birds may not mind messy nests, accumulating feces can pose risks for hatchlings:
Increased Parasites
Waste attracts parasites like mites and blowfly larvae. These can bite, irritate and even kill nestlings.
Bacterial Growth
Microbes thrive on the ammonia and nutrients in feces. This bacterial bloom releases harmful gases and can sicken chicks.
Soiled Plumage
Nestlings covered in feces may suffer matted, clumping feathers. This can reduce insulation and make them ill.
Parental Abandonment
At a certain point of excess feces, parents may abandon the nest and starved young. Maggoty parasites may have a similar effect.
However, nestlings have some defenses too:
Immune Defenses
As nestlings age, their immune systems better resist pathogens from feces and parasites.
Frequent Feedings
Well-fed nestlings have energy reserves to withstand minor nest parasites.
Older Nestlings Move
Larger nestlings can move to avoid direct contact with feces beneath them.
Despite these mitigating factors, soiled nests clearly increase risks to developing chicks. While birds may tolerate more than humans, excess waste accumulation causes higher nestling mortality.
Do Some Bird Species Keep Cleaner Nests?
While most birds do not actively remove waste from nests, some species have adapted behaviors that may help limit unsanitary conditions:
Hole-Nesters
Species nesting in tree cavities or artificial boxes allow feces to drop down through chamber below.
Colony Nesters
Social birds like cliff swallows may frequently abandon old nests to build fresh ones.
Open-Cup Remodelers
Robins, thrushes and other open-nest builders often construct a new nest liner over old soiled lining.
Precocial Young
Meadowlarks and killdeer have mobile young that can move out of nests sooner, limiting soiling.
Frequent Sanitizers
Pigeons, doves and other taxa regurgitate crop milk to sanitize young and keep nests clean.
So while no birds have evolved cleaning behaviors like cats, some species’ strategies may help limit prolonged contact with waste matter. Overall though, tolerance for normal nesting conditions remains the rule across most bird families.
Conclusion
In summary, active poop removal is not an instinctive behavior in parent birds. Nest hygiene does not appear to be a priority versus feeding and protecting young. However, some natural side effects can incidentally clean nests to a degree. Excessive feces buildup does increase health risks and mortality for developing chicks. But evolution has allowed most species to tolerate messier conditions than humans typically would. Some unique nesting behaviors in certain bird groups may help limit unsanitary nest situations. Overall though, bird nests remain functioning, effective places to rear young in spite of accumulated waste. So while not pristine, natural levels of feces appear not to bother the vast majority of attentive bird parents.
