NEW YORK (TheStreet) -- For dividend income, it is tough to beat Big Oil stocks such as BP (BP) - Get Report, ConocoPhillips (COP) - Get Report, and Royal Dutch Shell (RDS-B). What makes BP, ConocoPhillips, and Royal Dutch Shell even more attractive for long-term investors is how much more the stock prices fluctuate than the average for the market. As a result, patient investors should have the opportunity to buy when the share price is lower with the dividend yield that much higher.

This method for buying dividend stocks was detailed in a previous article on TheStreet, "Hunting for Higher Dividends."

Stocks with a high beta move more than the market as a whole, which has a beta of 1. When the share price drops, the dividend yield becomes that much higher. The beta for BP is 1.62. That means that the stock price moves 60% more for BP than the overall stock market. For Royal Dutch Shell, beta is 1.08. ConocoPhillips has a beta of 1.08.

Having a higher beta hardly means that these companies have a higher risk of failure, though.

Royal Dutch Shell, with a market capitalization of $232.6 billion, is the second largest oil and natural gas company in the world behind only Exxon Mobil (XOM) - Get Report, at $435.8 billion. But Royal Dutch Shell has more annual sales ($460.04 billion) than Exxon Mobil ($424.71 billion). BP has almost as much in annual sales ($400.93 billion) as ExxonMobil, too. With more than $60 billion in sales, ConocoPhillips also has a solid place in the global energy market.

The dividend income component of BP, ConocoPhillips and Royal Dutch Shell really impresses.

The dividend yield for BP is 4.73%. For Royal Dutch Shell, it is 4.64%. ConocoPhillips provides a stream of dividend income to its shareholders at a 4.09% rate.

Due to how much the shares move for these equities, investors can buy the stock at a lower price with a higher dividend yield.

Now trading around $48.50 a share, BP is right around its 52-week high of $49.20. When it was at its low of $38.51, the dividend yield was much higher. While it is impossible to time the market so as to buy at the lowest price, investors can put in purchase orders to execute at certain dividend yields.

As an example, if a 5% dividend yield is desired, more than 250% higher than the S&P 500's average, BP would need to be selling around 5% lower. A buy order for that target price, under $46, could have been transacted in any month in 2013. In addition, BP has raised its dividend every year since 2011, so the yield should rise even more based on the actions of the management of the company in the past.

The same can be done with ConocoPhillips and Royal Dutch Shell. Through this, the stock is bought at a lower price with a higher yield. For investors willing to wait to purchase shares at a target dividend rate, the total return can be much more rewarding when the share price recovers and the dividend grows over the long term.

At the time of publication, the author held no positions in any of the stocks mentioned.

This article represents the opinion of a contributor and not necessarily that of TheStreet or its editorial staff.

Jonathan Yates has written for numerous publications including Newsweek and The Washington Post. He is a former general counsel for a publicly traded corporation. Much of his career was spent working on Capitol Hill for Members of Congress in both the House and Senate. He has degrees from Harvard University, Georgetown University Law Center and The Johns Hopkins University.