While it may would seem logical that a parent who is incarcerated in either prison or jail would lose their parental rights while locked up, that's not necessarily the case.
A prisoner may lose many many different civil rights while serving time for a crime they've committed, but visitation and parental rights aren't included on the list. Many times it takes the custodial parent going to court and requesting that a judge legally terminates the incarcerated one's visitation or parental rights for them to no longer be entitled to see their child.
Although a parent who is locked up is legally entitled to continue having a say in their child's life, a spokesperson with the Center of Children of Incarcerated Parents (CCIP) warns that this is a mere technicality on paper.
They note that most children can't drive themselves to go see an incarcerated parent. Instead, they must rely on their other parent to take them.
When calls come in, whether or not the child is able to speak their parent who's in jail greatly depends on whether the non-incarcerated parent passes the phone to them. Whether they receive any mailed letters also depends on whether the non-incarcerated parent lets them have it.
CCIP warns that prisoners often find themselves in a disadvantageous position for maintaining lines of communication between them and their kids. There are currently no existing laws requiring a non-incarcerated parent to bring their child to a jail for visitation with their other parent. While a prisoner could hire an attorney to file a lawsuit to request visits at jail by his kids, it may be cost-prohibitive to do so.
Once a parent is incarcerated, the the custodial one is still obligated to seek out the jailed one's permission for major surgeries and other events unless sole legal custody has been awarded. A petition must be filed with the court and a decree made a judge for the non-incarcerated parent to be allowed to make decisions for their child.
Requests can also be made to have your ex's parental rights stripped. Your ex justifying why he or she should retain them may be an uphill battle to fight depending on the crime he or she has been convicted of.
If you share kids with an ex that is currently incarcerated, then a Fort Myers child custody attorney can advise you of options that can be pursued in your case.
Source: Livestrong, "Parental rights of a father in jail," J.E. Myers, accessed March 30, 2018