Hidden Hazards: Plants, Foods & Sea Creatures That Can Harm Your Dog

Dogs are naturally curious, which is one of the many things we love about them. But that curiosity can lead to trouble when it comes to the plants they sniff, the scraps they sneak, or even the strange things they discover on the beach.

Here in New Zealand, we might not have native snakes or deadly spiders lurking in our backyards, but that doesn’t mean our dogs are out of the woods. From toxic garden plants to harmful human foods and venomous sea snakes, danger can still be hiding in plain sight.

Let’s break down the most common risks and how to keep your pup safe.

Toxic Plants in NZ Gardens

New Zealand gardens are full of beautiful native and imported plants, but several of them are dangerously toxic to dogs. Here are the key culprits:

1) Karaka Tree

Native to NZ, the orange berries from the karaka tree contain karakin, a potent neurotoxin that can cause vomiting, seizures, and in severe cases, death.

2)  Yew

Used in hedging, yew is extremely toxic. Even a small amount can cause tremors, heart issues, and sudden death.

3)  Foxglove

While beautiful, foxglove contains compounds that affect heart function. Ingestion may lead to vomiting, drooling, and cardiac arrest.

4)  Oleander

All parts of the plant are toxic and can result in digestive issues, heart irregularities, and collapse.

5)  Lily species

Highly toxic to cats and potentially harmful to dogs. Even brushing against the pollen can be dangerous.

6)  Ragwort

Commonly found in paddocks and roadside areas, ragwort causes liver damage in grazing animals and can harm dogs if ingested.

7)  Tutu

Another native shrub with small black berries and red stems, tutu contains tutin, a neurotoxin that can lead to tremors and seizures.

8)  Rhubarb Leaves

The leaves (not the stalks) are rich in oxalates and can damage kidneys and cause serious illness in dogs.

Tip: Supervise your dog outside and remove or fence off known toxic plants. When landscaping, opt for pet-safe options like kōwhai, native grasses, or hebe.

Human Foods That Are Dangerous for Dogs

Some of our favourite snacks and meals are toxic for dogs, even in small amounts:

• Chocolate: contains theobromine, which can cause heart issues, tremors, and seizures.
• Grapes & Raisins: can cause sudden kidney failure (also found in hot cross buns!).
• Onions & Garlic: damage red blood cells and may cause anaemia.
• Xylitol: an artificial sweetener in gum and sugar-free treats; can cause liver failure and hypoglycaemia.
• Avocados: contain Persin, which may cause stomach upset.
• Macadamia Nuts: cause weakness, tremors, and vomiting.
• Cooked Bones or Corn Cobs: risk of choking and intestinal blockage.
• Alcohol & Raw Yeast Dough: even small amounts can lead to dangerous bloating and alcohol poisoning.

If you suspect your dog has eaten something toxic, call your vet or the Animal Poisons Helpline (0800 869 738) right away.

Beach Danger for Dogs in New Zealand

A day at the beach might seem like the perfect dog-friendly outing, but hidden hazards can quickly turn fun into an emergency. Here’s what to watch for:

1) Sea Snakes

Yellow-bellied sea snakes are appearing more frequently on NZ beaches, especially after storms. They’re highly venomous, even when dead. If your dog bites or chews one, venom can enter through the gums or tongue, potentially causing collapse, seizures, or death.

2) Shellfish & Dead Marine Life

Dogs are natural scavengers and may eat washed-up crabs, pufferfish, mussels, jellyfish, or other creatures. These may contain bacteria, parasites, or toxins. Pufferfish are especially dangerous due to tetrodotoxin, which is deadly even in small amounts.

3) Food Waste & BBQ Leftovers

Popular beaches often have litter: chicken bones, skewers, corn cobs, grapes, and even wrappers or plastic bags—all of which can be choking or poisoning hazards.

4) Sharp Objects

Broken glass, sharp shells, and discarded fishing hooks are common hazards. Dogs can easily cut their paw pads or ingest dangerous items.

5) Strong Currents & Surf

Even confident swimmers can get swept away by rip currents. Flat-faced breeds (like pugs and bulldogs) and older dogs are particularly at risk.

6) Sunburn & Heatstroke

NZ has some of the world’s highest UV levels. Dogs, especially short-haired, white-coated, or pink-skinned, can burn easily. Overheating is also a real concern on hot days.

7) Toxic Algae

Often found in rivers and estuaries, especially during summer. Ingestion can cause vomiting, seizures, liver failure, and even death. Check your local council’s water quality alerts before letting your dog swim.

8) Sand Ingestion

Dogs who dig, chase balls, or lick sand off toys may accidentally ingest too much. This can lead to sand impaction, a painful and dangerous blockage in the gut.

9) Hot Sand and Pavements

If the ground is too hot for your bare feet, it’s too hot for your dog’s paws. Burns can occur quickly and go unnoticed until it’s too late.

10) Contaminated Water or Faeces

Drinking from stagnant pools or eating other animals’ faeces can expose dogs to Giardia, E. coli, or parasites.

Protect Your Pup With Petcover

Accidents happen, no matter how cautious we are. That’s where Petcover can help. Our policies are designed to support you through unexpected emergencies, whether it’s a toxic plant, a sneaky snack, or a scary moment at the beach.