This project is directed towards implementing aspects of the tidewater goby recovery plan in coordination with, and funded by, the US Fish & Wildlife Service (USFWS) through a Section 6 Cooperative Agreement awarded to the University of California, Los Angeles on May 15, 2015. The primary focus of this dissertation was to developed a quantitative framework to complete a metapopulation viability analysis (MVA) for the endangered tidewater gobies in the genus Eucyclogobius. Modeling tidewater goby metapopulation dynamics is an essential component in constructing long-term management plans rangewide throughout the California Coast. This dissertation examines more closely how these dynamics affect viability, connectivity, and long-term persistence of tidewater goby metapopulations throughout the California coast. In the first chapter of this dissertation, I conducted annual population surveys (2014, 2015, and 2017-2018) in 117 estuaries and lagoons to assess the current health and status of the tidewater gobies in five of the six Recovery Units, spanning from Bodega Bay to San Diego, CA. This massive effort has provided continuous coastal surveys over four years, and over 300 observations, which helped create the framework for a robust and comprehensive presence/absence dataset to help inform metapopulation management and recovery actions. In the second chapter of this dissertation collated all existing rangewide occupancy data, metapopulation descriptors, wetland site characteristics, and repository specimen collections into an open access database. This database will provide critical information relative to the federally endangered tidewater gobies and help inform the metapopulation viability analysis model developed in this study, as well as support continued research on the conservation and management of these incredible fish species and the coastal wetland ecosystems they inhabit. In the third chapter of this dissertation I review the general biology, conservation status, habitat impacts, and metapopulation dynamics of the northern tidewater goby (Eucyclogobius newberryi) and southern tidewater goby (Eucyclogobius kristinae). In addition, I demonstrate the effectiveness of a Bayesian approach to provide a flexible method to generate metapopulation viability analyses and provide a detailed summary of the MVA model framework, including limitations, required corrections, and future amendments that need to be addressed in order to meet the recovery criterion envisioned in the recovery plan.