Why have my hens stopped laying?

🐔 The short version

Most drops in lay are normal. Rule those out first.

When the egg basket comes back lighter than usual, it is natural to assume something is wrong with the birds. Usually nothing is. The most common reasons hens lay less are the time of year, a moult, their age and a broody hen — all normal, all expected, and none of them needing a vet.

The next group is things you can fix: not enough water, a diet watered down with grain or scraps, mites or lice, heat, and stress. After that come eggs that are being laid but going somewhere else. Illness is real and matters, but it is rarely the first explanation — and when it is, it usually comes with other signs you can see.

So work down the list in that order. This guide goes through each one, what it looks like, and what to do about it.

🔎 Before anything else

Start with three questions.

You can narrow things down a long way before you go near a bird. Ask:

• Did it drop suddenly or gradually? Over a few days, or over several weeks?
• Is it the whole flock, or one or two hens? If you can tell who is laying — by egg colour, or by who is sitting in the nest box — that helps a lot.
• What month is it? The same drop means different things in April and in October.

That last row matters most. A drop in lay alongside birds that are quiet, off their feed, sneezing, scouring or dying is not a laying problem, and the rest of this list can wait.

☀️ The biggest one

Is it the time of year?

Hens lay in response to day length. The extension services put it plainly: hens need about 14 hours of light to keep laying well, and once days fall below about 12 hours, production drops and often stops. Lengthening days switch laying back on; shortening days slow it down.

Most of that research comes from North America, and here is where New Zealand differs. Across most of the country, we only get 14 hours of daylight for a few months in the middle of summer. In Northland it is barely ten weeks.

Sunrise to sunset, worked out from standard sun-position equations. Usable light at dawn and dusk adds a little.

Two things follow from that table.

First, a slow-down from February onwards is expected, not a fault. The days are already shortening by late January, and everywhere in the country drops below 12 hours in the last week of March. Autumn and winter are the low season for backyard eggs, full stop. A flock that lays lightly through June and July is doing what hens do.

Second, the direction is what matters. Days pass 12 hours around the spring equinox in late September and climb from there, so a healthy flock should be picking up through spring. If your numbers are falling in October or November, daylight is almost certainly not the reason — keep working down this list.

🪶 Feathers everywhere

Are they moulting?

Once a year, hens drop their old feathers and grow new ones. Feathers are almost pure protein, and a hen cannot grow a new coat and lay eggs at the same time — so laying stops while she moults.

• When: triggered mainly by shortening days, so in New Zealand that means autumn, roughly March to May. Stress can set one off at any time of year.
• Who: the first full moult usually comes at around 18 months old, and then yearly after that. Hens in their first laying season usually skip it.
• How long: most moults take about eight weeks from feather loss to new feathers, but anywhere from one to three months is normal. Older hens tend to moult more often.
• What it looks like: feathers lost from the neck, breast and back, a scruffy look, and a lot of feathers in the run. New feathers come through as pin feathers, like little quills.

Moulting is a rest period, and there is not much to do except make it easier. Texas A&M's vet school suggests a feed of about 20% protein is usually enough through a moult; many keepers mix some meat-bird or grower crumble into the usual feed for a few weeks. Handle moulting birds as little as you can — the new feathers are sensitive.

📉 The slow one

Are they getting older?

Hens lay the most in their first year. Pullets usually start at 18–22 weeks depending on breed, and University of Florida figures put a flock at a peak of about 90% lay six to eight weeks after that, easing to around 65% by the end of the first year. Laying stays reasonable for two or three years and then declines steadily. Older hens also moult more often.

So a flock that laid well three springs ago and is laying noticeably less now is probably not sick. It is getting older. There is nothing to fix here, only a decision to make, and it is yours: some people keep older hens for as long as they live, some bring in a few young birds each year so the laying never drops too far, and some cull. What an older hen actually costs you is easy to work out if you know what the flock eats and what it lays — more on that at the end.

🥚 Sitting tight

Has someone gone broody?

A broody hen has decided it is time to hatch chicks. She stops laying, sits flat in the nest box nearly all day, puffs up and growls or pecks when you reach under her, and gets off only briefly to eat, drink and leave a very large dropping. She may sit on nothing at all.

Some breeds are far more prone than others — Silkies and Cochins are famous for it, and it is rare in Leghorns and many modern layer hybrids. Left alone, a broody spell can last three to six weeks, and she lays nothing the whole time.

If you don't want chicks:

• Collect eggs every day, and check any hidden spots too, so there is nothing to sit on.
• Lift her off the nest each time you see her there.
• If that doesn't work, keep her away from the nest for several days — a separate pen or cage with food and water but no nest box. Most hens give up and go back to laying afterwards.

If you do want chicks, a broody hen is the easiest incubator there is. Either way, it is one of the few causes of a drop you can spot in ten seconds.

🌾 What goes in

Is it the feed or the water?

Water first, because it is the quickest to cause a drop and the easiest to miss. An egg is mostly water, and a hen drinks roughly twice as much water as she eats in feed. University of Florida's extension service calls water "probably the most essential nutrient", and notes that going without for several hours will probably cause a drop in lay. A drinker knocked over, frozen, fouled or run dry on a hot afternoon can cost you eggs for days afterwards. Our stock water guide has the figures.

Then feed. Laying hens need a complete layer feed with around 16–18% protein and plenty of calcium. The common ways that goes wrong:

• Too much grain or scraps on top. Hens eat until their energy needs are met, so wheat, maize and scraps replace layer feed rather than adding to it. The protein and calcium get watered down, and lay can drop. Our guide on what to feed laying hens explains how this happens. A handy rule: extras only as much as the birds clear in about 15 minutes.
• A change of feed. A new brand, a new batch or a switch from pellets to mash can put hens off for a few days. Change over gradually by mixing the old and new.
• The wrong feed for the job. Starter and grower feeds aren't made for laying hens. They are useful during a moult, but not as the everyday feed for a laying flock.
• Not enough calcium. Usually shows first as thin or soft shells rather than fewer eggs. A separate container of shell grit, offered free-choice, covers it.
• Old or mouldy feed. Feed loses quality in storage. Buy what you'll use in a month or so and keep it dry and sealed.

Feed problems usually show over weeks rather than days, which is why they are easy to miss. If you changed anything about the feed in the last month, write down when — it is the first thing to check.

🔦 Take a torch

Could it be mites or lice?

Mites and lice are easy to miss because the worst of them are hard to see in daylight, and a heavy load drags egg numbers down with no other obvious sign. University of Florida puts the drop from lice at up to 10%, and as much as 20% in heavy infestations.

• Red mite is the sneaky one. According to the Merck Veterinary Manual, red mites feed only at night and spend the day hiding under droppings, on roosts, in nest boxes, and in cracks and crevices in the coop. The birds can be carrying a heavy burden and you'd never see a mite on them at midday. Go out after dark with a torch and look along the perches and in the nest boxes, especially the ends and joints. Pale combs, hens reluctant to go into the coop at night and hens avoiding the nest boxes are all worth noting.
• Northern fowl mite lives on the bird. Part the feathers around the vent: crusty, scabby skin and dirty feathers there are the giveaway. Merck notes that even moderate numbers — over 100 mites per bird — can reduce laying.
• Lice also live on the bird. Look at the base of the feathers around the vent and under the wings for crawling insects and clusters of eggs.

Treat the birds and the coop — red mite especially lives in the building, not on the hen. Use a product registered for poultry, follow the label, and check the egg withholding period before you eat or sell eggs from treated birds. Your vet or a rural supply store can tell you what's registered here.

Worms are worth a mention too. A heavy worm burden can slow laying, and birds that range on the same ground for years build one up. It is less common than mites as the reason for a sudden drop, but if the birds look thin despite eating well, ask your vet about a faecal egg count.

🌡️ Upsets

Heat, fright and changes in the flock.

Hens are creatures of habit, and a lot of ordinary things put them off the lay for a few days to a couple of weeks. The extension services list moving, handling, chilling, overheating, fright, predators and changes to the flock's social order.

• Heat. In hot weather hens eat less, and laying drops with it. Birds panting with their wings held out from their bodies are too hot. Shade, airflow through the coop and cool, clean water in more than one place all help.
• A fright. A dog getting into the run, a harrier hawk sitting on the fence post, a ferret or stoat at night — even without a bird being lost, a scare can knock laying back for days.
• New birds, or birds removed. Every change to the flock resets the pecking order, and the squabbling that follows costs eggs. Hens at the bottom of the order may be kept off the feeder and nest boxes. Before new birds join, read our guide to buying and quarantining new stock — a new bird can bring mites or disease in with her.
• Moving house. Hens moved to a new coop, or a whole flock bought in, often stop laying for a while as they settle.

The good news with all of these is that they fix themselves once the cause goes away. The trick is noticing the cause — which is much easier if you know what date the drop started.

🕵️ Laid but not found

Are the eggs being laid but not found?

Sometimes the hens are laying just fine and the eggs are going somewhere else. If the birds look healthy, busy and well-feathered, with red combs, but the basket is light, check these before anything else.

• Hidden nests. Free-ranging hens are very good at finding a quiet spot under a hedge, in long grass, behind the woodpile or in the hay shed. One hen with a secret nest can take a real bite out of a small flock's count. Watch where they go mid-morning, and keep the birds shut in until late morning for a few days so they relearn the nest boxes.
• Egg eating. A hen that finds a broken egg and eats it can make a habit of it, and others copy. Signs are broken shells or yolk in the nest boxes, or yolk on a hen's beak. Collect eggs more often, make sure nest boxes are dark and have plenty of bedding, keep shells strong with shell grit, and a ceramic or dummy egg in the nest can put them off.
• Something else taking them. Rats take eggs from nest boxes, as can dogs, and some farm dogs learn it well. Look for droppings and tunnelling around the coop and feeder.

🚩 When to worry

When a drop means something is wrong.

A drop in egg production is often one of the first signs of disease. What separates it from everything above is what else you can see. Get help if the drop comes with any of these:

• Birds that are quiet, hunched, slow to move, or not eating
• Coughing, sneezing, gasping, rattly breathing or runny noses and eyes
• Watery, green or bloody droppings
• Swollen heads, faces or wattles, or combs that are pale or purple
• A sudden run of thin-shelled, soft, wrinkled or misshapen eggs across the flock
• Birds dying without an obvious cause — especially several at once

For a sick bird or two, call your vet. Some respiratory diseases present in New Zealand can cut laying sharply — University of Florida puts the drop from infectious bronchitis at up to 50%, with misshapen and soft-shelled eggs — and a vet can tell you what you're dealing with.

📲 Knowing, not guessing

Why a daily count makes this easier.

Look back at the three questions at the top: sudden or gradual, whole flock or a few birds, what month. Each one is easy to answer with a written record and hard to answer from memory. "They've been off a while" could mean ten days or two months, and those point to completely different causes.

A daily egg count, written down for each flock, gives you:

• The date it started, so you can line it up against a feed change, a hot spell, new birds or the day the dog got in.
• The shape of it — a cliff or a slope.
• Which flock, if you keep more than one.
• Your own normal, season by season, so next autumn's dip is something you expected rather than something that worries you.

It also tells you what the drop is costing. The hens eat roughly the same amount whether they lay or not, so when laying halves, the cost of each egg roughly doubles. That is the number that tells you whether a problem is worth spending money on, and whether an older hen is still paying her way.

That is what My Block Hand does for a flock. Log eggs each day — one row per flock, a couple of taps at the back door — and each flock shows its eggs over the last 7 and 30 days, eggs per bird, and a status that changes to Low production when the numbers fall. Add feed purchases and it works out your cost per egg.

🚧 Where this guide stops

What this guide cannot do for you.

This is general information for lifestyle-block and backyard poultry keepers. It is not veterinary advice. The figures here come from published extension and veterinary sources listed below; your birds, breed and block will vary.

If birds are unwell, a drop is sudden and unexplained, or you are seeing deaths, talk to your vet — and for unexplained deaths, MPI on 0800 80 99 66. For any treatment, follow the product label, including the egg withholding period.

📚 Further reading

Where the information on this page comes from.

• Virginia Tech Extension 2902-1097 — Why Have My Hens Stopped Laying? (Jacobs & Clauer): 14 hours of light to sustain lay and the decline below 12 hours; age-related decline after two or three years; 16–18% protein; stress factors; a drop in lay as an early sign of disease.
• University of Florida IFAS PS029 — Factors Affecting Egg Production in Backyard Chicken Flocks: laying from 18–22 weeks, the ~90% peak easing to ~65% after 12 months, water as "probably the most essential nutrient", heat stress, lice (10–20%) and infectious bronchitis (up to 50%).
• Oregon State University Extension PNW 565 — Why Did My Chickens Stop Laying?: 14–16 hour days for peak lay, the six-week winter lights-off rest, production declining after 2–3 years, how to break a broody hen, breed differences in broodiness, and the 15-minute rule for extras.
• University of Arizona Extension — Nine Common Reasons Your Hens Aren't Laying: broodiness lasting 3–6 weeks, egg eating, hidden laying spots and heat reducing feed intake.
• Texas A&M College of Veterinary Medicine — Hen molting: moult length (about eight weeks, one to three months), the first full moult at about 18 months, day length as the trigger, and a ~20% protein diet during moult.
• University of Georgia — Backyard flock newsletter, November 2007 (PDF): where feathers are lost in a natural moult, and moult as a rest period.
• Merck Veterinary Manual — Mites of Poultry: red mite feeding at night and hiding in droppings, roosts, nest boxes and cracks by day; northern fowl mite around the vent, and reduced lay at over 100 mites per bird.
• University of Kentucky Extension ASC233 (PDF): the water-to-feed ratio and reduced lay after a shortage of water.
• Ministry for Primary Industries — Bird flu and protecting your birds: the signs of bird flu in poultry, sudden deaths as an early sign, and reporting to 0800 80 99 66.
• NOAA Solar Calculator: the sunrise and sunset equations behind the New Zealand day-length table.