17 years of Recovery Data for Marked Mussels inp suggestions

[G3isMe]

I am modeling freshwater mussel survival. Two-hundred fifty individuals of three species of mussels were marked in 1996 and we recovered them as either live or dead animals in 1997, 98, 99, and 2000. We were unable to return to the site until 2013, 17 years after they were originally marked. We recovered (both live and dead animals) 30% of species A, 25% of species B, and 5% of species C. In March of 2000 I contacted Dr. White and we discussed how best to analyze survival of these animals. He suggested and I used a Burnham model with LD coding with 1=live in recovery year, 0 = live in interval, 1 = dead in interval followed by a 0 in year. For example my inp file would look something like the following for some of the possible scenarios:

/*1996 interval 1997 interval 1998 interval 1999 interval 2000 interval Num*/
1 0 1 0 1 0 0 0 1 0 1; Live throughout capture history
1 0 1 1 0 0 0 0 0 0 1; Dead recovered in 1998
1 0 1 0 0 0 0 0 0 0 1; Missing since 1997



For my previous analysis I did not include animals which were marked and never recovered again. This was only a couple of animals. I also have ages of the animals at the time of marking. Since mussels lay an annual growth ring much like a tree, I can estimate the year that the recovered dead mussels died and hence format my new inp file accordingly.

My questions are what are your thoughts on estimating the population survival rate using only those animals which were recovered in 2013 under the assumption that animals not recovered survived at the same rate as those which were recovered? Or conversely should I include all of the animals and code them as not recovered? Thanks in advance!
Rick