"Fewer consumers are going into branches. In the branch, it can no longer be about basic transacting," she suggested. "A financial institution needs experts who can sell in those positions."

More fuel comes from teller studies such as the one by Financial Management Solutions Inc., which documented a startling 124% jump in unit labor cost per transaction over the past 22 years.

"[Financial institutions] are paying employees more and allowing them to be less productive. This rising trend is likely to continue due to a continuing reduction in transaction activities," according to the FMSI report.

In its salary and benefit analysis, FMSI found that tellers, on average, are paid $16.55 per hour. Multiplied many times over, that wage has attracted the interest of cost cutters at some financial institutions.

"Teller salaries are a significant expense," Nate Tobik, founder/CEO of CompleteBankData.com, a financial institution data tracking firm in Pittsburgh, Pa., said. "Many financial institutions want to reduce those costs."

Yet, more fuel comes from the fact that in a digital age, consumers are doing much more self-serve transactions. Checks are deposited via mobile remote deposit capture on cellphones that can now create scans of items.

Indeed, transactions are less reliant on face-to-face interactions. Many consumers get their cash from ATMs, not tellers. Branch visits and teller interactions are also on a steady downward plummet, according to some reports. Still, the teller position is long from becoming passé.

"I do not see much removal of tellers," Sabeh Samaha, CEO of the Chino Hills, Calif.-based consulting firm Samaha Associates. "This [reduction in the teller force] will happen slowly on the credit union side."

Read more: Navy Federal beefing up branches …

Broad agreement about continuity in teller ranks comes from the Bureau of Labor Statistics' Occupational Outlook Handbook, which noted there were 545,300 tellers in the U.S. in 2012. The outlook for 2022 was over 1%, meaning little to no change, according to the BLS report.

Some credit unions are, in fact, going the other way and widening their teller ranks.

"Navy Federal is expanding our branch network over the next few years to provide members with greater and easier access to products and services," Kathy Ward, SVP of operations at the $60 billion Navy Federal Credit Union in Vienna, Va., said.

Member service representatives or commonly, tellers, are an essential part of the overall member experience and an important part of product service within the credit union's branches, Ward explained.

"We still have a significant number of people who join Navy Federal through the branches, and our member service representatives are there to help facilitate that membership."

At the other end of the spectrum, the $34 million 1st Valley Credit Union in San Bernardino, Calif., anticipated some, but not any dramatic change in the size of its teller ranks, according to CEO Gregg Stockdale.

Since 2010, the depth of the recession in California's Inland Empire led to reducing 1st Valley's teller ranks by two while others had had their hours cut from full-time to part-time, Stockdale said. However, there will always be a need for these employees, he predicted.

"We'll probably have tellers as long as we have credit unions. Certain members and memberships are into personal service," he said. "Not everyone does busness overtheir cellphone or the Internet. We are transitioning downward in our teller. I'm not sure where the bottom will be for us, but it won't be zero for a long time."

Read more: Kiosks and training modernize branches …

The $412 million Connex Credit Union in North Haven, Conn., has been deploying interactive teller machines at some of its branches, Carl Casper, vice president of customer advocacy, said.

ITMs or virtual teller machines typically allow members to conduct automated transactions while interacting with member service representatives via video. By tapping a touchscreen members can make deposits and withdrawals, cash checks and make account payments among other transactions.

With the credit union's ITM deployment, tellers at two of the credit union's seven branches have been moved to a central location.

"We are doing this as leases come up," Casper explained. "Long term, we will get all our tellers into a back office."

In the process, the credit union's branch footprint has shrunk from more than 2,000 square feet to between 400 and 500, he said.

The goal at Connex, Casper stressed, "is not teller elimination. It's to become more efficient."

The credit union also has a new in-branch job called a concierge to interact with members, help them get questions answered and to use the ITMs, which electronically connect members with a remote teller.

"Traditionally, a lot of credit unions have put tellers in a position where they are asked questions they are not equipped to answer," Casper said.

The plus of matching the ITMs with a concierge is that that members' questions can be directed to an employee who can genuinely help, he added.

Casper said there has been no widespread reduction in teller staff at Connex: "We have seen a one-body benefit."

Not every credit union is plunging into ITM technology.

"We are training up our tellers to become financial concierges. We are training them so they can answer more questions," Scott McFarland, president/CEO at the $575 million Honor Credit Union in St, Joseph, Mich., said.

"The transition has begun, it's changing in the background," he added. "Will there be a tipping point? Probably. But not soon."

The bottom line is change in teller ranks at credit unions is expected to come slowly.

"Like everything else in financial services, this will be a slow motion shift," Tobik said.

Some financial institutions, including credit unions, like deliberate change rather than abrupt alterations of course. Tobik suggested inevitably, transaction-oriented tellers will be displaced by problem solvers but that migration won't happen overnight or this year or next.

"It's happening but it will take time," he said.