diff --git a/src/simulator/crates/mc-ecology/Cargo.toml b/src/simulator/crates/mc-ecology/Cargo.toml
index 0d7921a7..34dfaeaf 100644
--- a/src/simulator/crates/mc-ecology/Cargo.toml
+++ b/src/simulator/crates/mc-ecology/Cargo.toml
@@ -10,7 +10,6 @@ gpu = ["dep:mc-compute"]
 mc-core         = { path = "../mc-core" }
 mc-climate      = { path = "../mc-climate" }
 mc-flora        = { path = "../mc-flora" }
-mc-mapgen       = { path = "../mc-mapgen" }
 mc-profiling    = { path = "../mc-profiling" }
 mc-compute      = { path = "../mc-compute", optional = true, features = ["gpu"] }
 serde.workspace      = true
diff --git a/src/simulator/crates/mc-ecology/src/fauna_select.rs b/src/simulator/crates/mc-ecology/src/fauna_select.rs
index 99767513..4533c0b8 100644
--- a/src/simulator/crates/mc-ecology/src/fauna_select.rs
+++ b/src/simulator/crates/mc-ecology/src/fauna_select.rs
@@ -9,7 +9,7 @@ use std::collections::{HashMap, HashSet};
 
 use serde::Deserialize;
 
-use mc_mapgen::seed::{SeedDomain, tile_rng};
+use mc_core::seed::{SeedDomain, tile_rng};
 
 // ── Constants ─────────────────────────────────────────────────────────────────
 
@@ -250,7 +250,7 @@ pub fn pick_fauna_for_tile(
 
     let normalised: Vec<f32> = weights.iter().map(|w| w / total).collect();
 
-    let domain_seed = mc_mapgen::seed::derive(map_seed, SeedDomain::FaunaSelect);
+    let domain_seed = mc_core::seed::derive(map_seed, SeedDomain::FaunaSelect);
     let mut rng = tile_rng(domain_seed, col, row);
 
     // Draw candidates
@@ -272,7 +272,7 @@ fn weighted_sample_fauna(
     eligible: &[&String],
     normalised: &[f32],
     max_count: usize,
-    rng: &mut mc_mapgen::seed::Pcg64,
+    rng: &mut mc_core::seed::Pcg64,
     specs: &HashMap<String, FaunaSpec>,
 ) -> Vec<SelectedFauna> {
     let n = eligible.len().min(max_count);
diff --git a/src/simulator/crates/mc-ecology/src/flora_select.rs b/src/simulator/crates/mc-ecology/src/flora_select.rs
index 0b94c8af..7b192bdf 100644
--- a/src/simulator/crates/mc-ecology/src/flora_select.rs
+++ b/src/simulator/crates/mc-ecology/src/flora_select.rs
@@ -12,7 +12,7 @@ use std::collections::HashMap;
 
 use serde::Deserialize;
 
-use mc_mapgen::seed::{SeedDomain, tile_rng};
+use mc_core::seed::{SeedDomain, tile_rng};
 
 // ── Aquatic / riparian species set ────────────────────────────────────────────
 
@@ -448,7 +448,7 @@ pub fn pick_flora_for_tile_stress(
     // Normalise by sum (never clip)
     let normalised: Vec<f32> = weights.iter().map(|w| w / total).collect();
 
-    let domain_seed = mc_mapgen::seed::derive(map_seed, SeedDomain::FloraSelect);
+    let domain_seed = mc_core::seed::derive(map_seed, SeedDomain::FloraSelect);
     let mut rng = tile_rng(domain_seed, col, row);
 
     weighted_sample_without_replacement(
@@ -465,7 +465,7 @@ fn weighted_sample_without_replacement(
     candidates: &[String],
     normalised: &[f32],
     max_count: usize,
-    rng: &mut mc_mapgen::seed::Pcg64,
+    rng: &mut mc_core::seed::Pcg64,
     specs: &HashMap<String, FloraSpec>,
 ) -> Vec<SelectedFlora> {
     let n = candidates.len().min(max_count);