diff --git a/ApiCore-Frontend/src/app/(app)/colonies/[id]/colony-actions.tsx b/ApiCore-Frontend/src/app/(app)/colonies/[id]/colony-actions.tsx
index 1119765..dcfda3a 100644
--- a/ApiCore-Frontend/src/app/(app)/colonies/[id]/colony-actions.tsx
+++ b/ApiCore-Frontend/src/app/(app)/colonies/[id]/colony-actions.tsx
@@ -48,7 +48,10 @@ function MoveDialog({ colony }: { colony: Colony }) {
   const queryClient = useQueryClient();
   const [open, setOpen] = useState(false);
   const [apiaryId, setApiaryId] = useState("");
-  const { data: apiaries } = useQuery({ queryKey: ["apiaries"], queryFn: () => fetchApiaries() });
+  const { data: apiaries } = useQuery({
+    queryKey: ["apiaries", { status: "ACTIVE" }],
+    queryFn: () => fetchApiaries({ status: "ACTIVE" }),
+  });
 
   const mutation = useMutation({
     mutationFn: () => moveColony(colony.id, { apiaryId }),
diff --git a/ApiCore-Frontend/src/app/(app)/colonies/new/page.tsx b/ApiCore-Frontend/src/app/(app)/colonies/new/page.tsx
index c746ab1..4311cd4 100644
--- a/ApiCore-Frontend/src/app/(app)/colonies/new/page.tsx
+++ b/ApiCore-Frontend/src/app/(app)/colonies/new/page.tsx
@@ -24,7 +24,10 @@ import { Card, CardContent } from "@/components/ui/card";
 export default function NewColonyPage() {
   const router = useRouter();
   const queryClient = useQueryClient();
-  const { data: apiaries } = useQuery({ queryKey: ["apiaries"], queryFn: () => fetchApiaries() });
+  const { data: apiaries } = useQuery({
+    queryKey: ["apiaries", { status: "ACTIVE" }],
+    queryFn: () => fetchApiaries({ status: "ACTIVE" }),
+  });
 
   const [code, setCode] = useState("");
   const [apiaryId, setApiaryId] = useState("");
diff --git a/ApiCore-Frontend/src/app/(app)/queens/[id]/assign-colony-dialog.tsx b/ApiCore-Frontend/src/app/(app)/queens/[id]/assign-colony-dialog.tsx
index 8acc5e9..b93a07a 100644
--- a/ApiCore-Frontend/src/app/(app)/queens/[id]/assign-colony-dialog.tsx
+++ b/ApiCore-Frontend/src/app/(app)/queens/[id]/assign-colony-dialog.tsx
@@ -3,6 +3,8 @@
 import { FormEvent, useState } from "react";
 import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
 import { assignQueenColony } from "@/lib/queens/api";
+import { QUEEN_UNAVAILABLE_STATUSES } from "@/lib/queens/labels";
+import { QueenStatus } from "@/lib/queens/types";
 import { fetchColonies } from "@/lib/colonies/api";
 import { Button } from "@/components/ui/button";
 import { Label } from "@/components/ui/label";
@@ -22,11 +24,18 @@ import {
   SelectValue,
 } from "@/components/ui/select";
 
-export function AssignColonyDialog({ queenId }: { queenId: string }) {
+export function AssignColonyDialog({
+  queenId,
+  queenStatus,
+}: {
+  queenId: string;
+  queenStatus: QueenStatus;
+}) {
   const queryClient = useQueryClient();
   const [open, setOpen] = useState(false);
   const [colonyId, setColonyId] = useState("");
   const { data: colonies } = useQuery({ queryKey: ["colonies"], queryFn: () => fetchColonies() });
+  const unavailable = QUEEN_UNAVAILABLE_STATUSES.includes(queenStatus);
 
   const mutation = useMutation({
     mutationFn: () => assignQueenColony(queenId, { colonyId }),
@@ -39,7 +48,13 @@ export function AssignColonyDialog({ queenId }: { queenId: string }) {
 
   return (
     <Dialog open={open} onOpenChange={setOpen}>
-      <DialogTrigger render={<Button variant="outline">Volk zuweisen</Button>} />
+      <DialogTrigger
+        render={
+          <Button variant="outline" disabled={unavailable}>
+            Volk zuweisen
+          </Button>
+        }
+      />
       <DialogContent>
         <DialogHeader>
           <DialogTitle>Königin einem Volk zuweisen</DialogTitle>
diff --git a/ApiCore-Frontend/src/app/(app)/queens/[id]/page.tsx b/ApiCore-Frontend/src/app/(app)/queens/[id]/page.tsx
index 1c62b5b..8624d0b 100644
--- a/ApiCore-Frontend/src/app/(app)/queens/[id]/page.tsx
+++ b/ApiCore-Frontend/src/app/(app)/queens/[id]/page.tsx
@@ -37,7 +37,7 @@ export default function QueenDetailPage() {
       <div className="grid grid-cols-1 items-start gap-4 lg:grid-cols-3">
         <div className="flex flex-col gap-4 lg:col-span-1">
           <QueenEditCard key={queen.id} queen={queen} />
-          <AssignColonyDialog queenId={queen.id} />
+          <AssignColonyDialog queenId={queen.id} queenStatus={queen.status} />
         </div>
         <div className="flex flex-col gap-4 lg:col-span-2">
           <div className="grid grid-cols-1 gap-4 xl:grid-cols-2">
diff --git a/ApiCore-Frontend/src/lib/queens/labels.ts b/ApiCore-Frontend/src/lib/queens/labels.ts
index 7562ce9..0dbf825 100644
--- a/ApiCore-Frontend/src/lib/queens/labels.ts
+++ b/ApiCore-Frontend/src/lib/queens/labels.ts
@@ -12,6 +12,17 @@ export const QUEEN_STATUSES: QueenStatus[] = [
   "DECEASED",
 ];
 
+// Mirrors the backend's QUEEN_NO_LONGER_AVAILABLE_STATUSES - a queen in one
+// of these statuses can no longer be assigned to a colony (the backend
+// rejects it), so the assign-colony UI disables itself instead of letting
+// the user hit that error after filling out the form.
+export const QUEEN_UNAVAILABLE_STATUSES: QueenStatus[] = [
+  "LOST",
+  "REPLACED",
+  "SOLD",
+  "DECEASED",
+];
+
 export const QUEEN_STATUS_LABELS: Record<QueenStatus, string> = {
   ACTIVE: "Aktiv",
   RESERVE: "Reserve",