Your Newly Adopted Rescue Dog Might Surprise You for Months
Bringing home a rescue dog is exciting, but it’s also challenging. You might expect your new pet to settle down within a few weeks. Here’s what research shows: how long does it take a rescue dog to adjust? A new study found that rescued dogs can keep changing their behavior for six full months after adoption. The good news? These changes are mostly improvements, and there are ways to help.
Researchers in Germany followed 158 rescue dogs that were adopted from abroad during their first six months in their new homes. The dogs came from different countries and backgrounds. Owners answered detailed questions about their dogs’ behavior at specific time points to track how things were changing. What the team discovered offers hope to anyone bringing home a rescue dog with an uncertain past.
Behavioral Improvement Takes the Full Six Months
The study’s big finding was clear: rescue dogs did not simply adjust to their new homes in a few weeks. Instead, their personality scores—how friendly, fearful, or reactive they were—improved steadily and significantly over the entire six-month period. This means that a dog who seemed fearful or withdrawn in week one might be much more relaxed and confident by month six. The researchers described these as “significant improvements,” though the study design (tracking dogs over time rather than comparing them to a control group) means we should see this as an association between time and improvement over the six months.
What this means for you: don’t judge your rescue dog too quickly. If your new dog seems nervous, overly cautious, or reactive in the first weeks, that behavior doesn’t define who your dog will become. Patience is part of the adjustment process. Owners often see their rescue dogs transform in ways they didn’t expect—becoming calmer, more sociable, and more confident as the months go on.
A Second Dog Can Make a Difference
One finding stood out in the research: living with another dog facilitated adjustment. This doesn’t mean every rescue dog needs a companion, but it does suggest that if you already have a calm, friendly dog at home, adding a rescue dog to the household may help the new arrival settle in more smoothly.
The other dog acts as a social guide. Your established pet shows the rescue dog how to move through the house safely, where the safe spaces are, and what normal household life looks like. This can lower anxiety and help the new dog learn the household routines faster.
That said, the study only measured this association—it didn’t assign dogs to live alone or with companions to compare the outcomes directly. So while the research points to a benefit, we can’t say with certainty that a second dog will always speed up adjustment for every rescue dog. Personality clashes, past trauma, or stress sensitivities could make a second dog unhelpful in some cases. Talk to your veterinarian about whether your specific rescue dog might benefit from a companion.
Understanding the Study’s Limits
This research followed rescue dogs imported into Germany, so the findings may not apply perfectly to all rescue dogs everywhere. The study relied on owner reports rather than direct observation of the dogs’ behavior, which means we’re measuring what owners noticed and remembered—not an objective lab test. Additionally, the owners providing information were generally committed enough to respond to multiple surveys, which might mean they were more patient or experienced than the average dog owner.
The study was observational, meaning researchers watched and measured what happened naturally rather than trying different adoption strategies on different groups of dogs. This is why we say dogs were associated with improvement over time, rather than saying time improved their behavior.
Practical Steps for Your Rescue Dog’s First Six Months
Set realistic expectations. Your rescue dog may seem like a completely different animal at month six than at week one. This is normal and usually a sign things are going well.
Provide a safe, quiet space. Give your rescue dog a room or area where they can retreat when overwhelmed. Crate training can help dogs feel secure if done gently.
Keep routines consistent. Predictable meal times, walk times, and playtime help anxious dogs feel safer and learn to trust their new environment.
Be patient with behavioral quirks. Fear, jumping, pulling on leash, or resource guarding may take weeks or months to improve. This is typical for dogs with uncertain backgrounds.
Consider consulting your veterinarian. If your rescue dog shows severe fear, aggression, or other concerning behaviors, your vet can rule out medical issues and recommend a professional dog trainer or behaviorist.
Six Months of Patience Usually Pays Off
Rescue dogs don’t adjust to their new homes overnight. A study of over 150 rescue dogs in Germany showed that behavioral improvements continued throughout the first six months after adoption. Your new dog may seem anxious or uncertain at first, but there’s a strong chance they’ll become noticeably calmer, more confident, and more bonded to you over time. If you already have a dog at home, that companion may help ease the adjustment. Above all, remember that rescue dogs often repay patience with loyalty and affection—sometimes it just takes a few months to see it.
This article summarizes peer-reviewed research for educational purposes. Always consult with your veterinarian for personalized advice about your pet’s health and behavior.
