As people flock to states like Florida and Texas for a warmer climate, someone they would rather not see is following them.

Of the top five states among reported identity thefts, all are in the southernmost regions of the country.

At the bottom of the list? North and South Dakota.

But don't blame the sunny skies. You might be surprised to learn what is really contributing to an identity theft problem that affects as many as 9 million Americans a year.

The majority of identity theft cases occur when thieves steal private personal data from a victim's computer, lift it from an unsecured WiFi network or online transaction, or hack the victim with viruses and other malicious software delivered through email phishing attacks, said Kevin Yu, vice president of operations at Scambook, an online complaint resolution platform.

Some states are particularly prone to these activities. Florida has the highest per capita rate of reported identity theft complaints, followed by Georgia, California, Arizona and Texas, according to a survey by Consumer Sentinel Network.

[InvestingAnswers Feature: 17 Shocking Facts About Identity Theft And Fraud In America]

The most commonly reported form of identity theft in these five states was government documents/benefits fraud, followed by employment-related and credit-card fraud. All of these states are densely populated, while states with low populations such as Montana, Maine, South Dakota and North Dakota ranked lowest on the list.

The question remains: Why do identity thieves target those southern states? Here are three explanations.

1. Reporting For Duty.

Members of the military are often targets for identity theft because they conduct their financial business online while overseas. They also tend to be slower to notice unauthorized credit card charges or suspicious activity because of extended training or deployment. Texas, California, Georgia and Florida are among the top states in the country with active duty military populations, according to the U.S. Census Bureau.

2. Laid-Back Snow Birds.

Florida has the highest population of adults older than 65, a demographic that is easy prey for cyber criminals because the elderly are less familiar with Internet and mobile technology. Senior citizens who are unaware of their personal security fall victim to scammers who file for false tax refunds in their name or obtain new lines of credit.

More than 17,500 identity theft complaints were reported in 2011 by residents in the Miami-Fort Lauderdale-Pompano Beach metropolitan statistical area.

3. Illegal issues.

In other regions, border states attract a higher immigrant population, which includes its share of illegal immigrants. To work in this country, you need a Social Security number, so many turn to the black market.

'If you're an illegal immigrant, that Social Security number is a dollar sign to you,' said Robert Siciliano, an identity theft expert and CEO of IDTheftSecurity.com.

Organized criminals earn millions of dollars by counterfeiting fake identification and selling them. Unfortunately, there are plenty of people out there willing to steal those numbers from their employers or hack databases to make a buck.

[InvestingAnswers Feature: 5 Secrets to Scare Away Identity Thieves]

Possibly most troubling is that people can legally access Social Security numbers through the Social Security Administration Death Master File, which contains information on more than 80 million deceased individuals with U.S. Social Security numbers. Shockingly, the index is public information. Siciliano said laws are being proposed to prevent that information from staying in the public realm.

Regardless of where you live, you can take steps to avoid becoming an identity theft victim.

Siciliano recommends a credit freeze: A new account can't be opened in your name unless you unlock the freeze. Protect your computer data by choosing strong passwords and installing anti-virus, anti-spyware, anti-phishing and firewall protections. Pay close attention to credit card statements and immediately report unauthorized activity. Or consider purchasing credit theft protection insurance, which runs $100 to $150 a year.

The good news is we don't all have to move to North Dakota to protect ourselves.

The Investing Answer: Keep tabs on your credit report to spot suspicious activities like new accounts that you didn't open. Watch those credit card statements for unauthorized charges and avoid giving out your Social Security number whenever possible.