FSRiver overrides my mapping

Hi, I am having an issue with FSriver and my mapping. I set up my index with its mapping, before I even set up the river. I can check the mapping at that point and it shows my mapping. However, once I start the river and it indexes data. The mapping has changed to FSriver's mapping. Does anyone have a fix for it or has anyone else seen this? Here is my elasticsearch stuff.

POST /docs/mydocs
{
"mappings":{
"properties":{
"title": "string",
"author": "string",
"content": "string"
}
}
}
PUT _river/helpriver/_meta
{
"type": "fs",
"fs":{
"url": "this is where my directory goes",
"includes": [".*doc", ".*docx"],
"update_rate": "10000"
},
"index":{
"index": "docs",
"type": "mydocs"
}
}
Thanks