Abstract: Delineating protected area boundaries and identifying key areas for target species are fundamental tasks in the development of a protected area system centered on national parks. Migratory waterbirds, characterized by high mobility, exhibit significant spatiotemporal dynamics in their annual cycle activities, posing considerable challenges to traditional static boundary planning. Taking the Yellow River Estuary National Park Candidate Area as a case study, this research integrated high-resolution satellite telemetry tracking data from 115 individuals of three threatened waterbird species, constructing 251 analytical samples (229 individual-season samples and 22 individual-year samples). The cumulative tracking duration reached 5324 days, yielding 941728 valid GPS location points. The study species included the Oriental Stork (Ciconia boyciana, n=101), the White-naped Crane (Antigone vipio, n=7), and the Swan Goose (Anser cygnoides, n=7). Utilizing the standardized analytical workflow of the R package track2KBA, the 50% core utilization distributions of individuals were extracted, sample representativeness at the population level was assessed, key distribution areas for each species were delineated, and the conservation coverage effectiveness and seasonal conservation gaps of the national park candidate area were quantitatively evaluated. The results demonstrated pronounced interspecific and seasonal differences in spatial utilization patterns and conservation effectiveness among species. For the Oriental Stork, sample representativeness reached 89%, 29%, 83%, and 78% in spring, summer, autumn, and winter, respectively. Its key area shifted dramatically with seasons. The summer key area contracted to 14 km², of which 83% (12 km²) fell within the candidate area boundaries. The key area identified in spring totaled 47 km², with 69% (32 km²) located outside the boundaries. The most prominent spatial mismatches occurred in autumn and winter, with total key areas reaching 55 km² and 58 km², and the proportions (and areas) of key area spilling over beyond the candidate boundary reaching 85% (47 km²) and 59% (34 km²), respectively. High-resolution satellite imagery visual interpretation further indicated that most key area outside the candidate area boundaries, thus not incorporated into the protected scope, were concentrated in areas adjacent to the protected land, river channels, reservoirs, and aquaculture ponds. In contrast, the interannual key areas for the Swan Goose (18 km²) and the White-naped Crane (4 km²) were highly concentrated in the southern portion of the study area, with 100% spatial coverage by the candidate area boundaries. By introducing standardized spatial utilization metrics (Relative Spatial Utilization Weights, RSUW) and demographic references (Individual Abundance Weights, IAW), this study established an evidence-based, objective research framework that translates animal tracking results into refined conservation planning. This approach can provide direct data support and decision-making references for refined spatial zoning, seasonal dynamic management, and boundary optimization adjustments within protected areas.