Installing gazebo_ros_pkgs for ROS2 on OSX

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I am trying to install gazebo_ros_pkgs for ROS2 on MacOS Catalina. I have managed to install Gazebo 11.3.0 and ROS2 Foxy Fitzroy but I am having trouble installing gazebo_ros_pkgs. The tutorial only gives instructions for Ubuntu and I am not sure how to adapt this to my system.

Any advice?

Edit: More detail as requested below. On the rosdep install --from-paths src --ignore-src -r -y step I get the following output (all steps before work as expected):

ERROR: the following packages/stacks could not have their rosdep keys resolved to system dependencies: gazebo_dev: No definition of [libgazebo11-dev] for OS [osx] cv_bridge: No definition of [python3-opencv] for OS [osx] Continuing to install resolvable dependencies... #All required rosdeps installed successfully

The colcon build --symlink-install then returns:

Starting >>> camera_calibration_parsers
Starting >>> cv_bridge
Starting >>> gazebo_dev
Starting >>> gazebo_msgs
Starting >>> image_transport
Starting >>> image_geometry
--- stderr: cv_bridge
CMake Error at /usr/local/lib/cmake/Boost-1.74.0/BoostConfig.cmake:141 (find_package):
Could not find a package configuration file provided by "boost_python"
(requested version 1.74.0) with any of the following names:

boost_pythonConfig.cmake  
boost_python-config.cmake

Add the installation prefix of "boost_python" to CMAKE_PREFIX_PATH or set
"boost_python_DIR" to a directory containing one of the above files. If
"boost_python" provides a separate development package or SDK, be sure it
has been installed.
Call Stack (most recent call first):
/usr/local/lib/cmake/Boost-1.74.0/BoostConfig.cmake:258 (boost_find_component)
/usr/local/Cellar/cmake/3.19.1/share/cmake/Modules/FindBoost.cmake:460 (find_package)
CMakeLists.txt:22 (find_package)

---
Failed <<< cv_bridge [3.26s, exited with code 1]
Aborted <<< gazebo_dev [3.30s]
Aborted <<< image_geometry [5.76s]
Aborted <<< image_transport [6.38s]
Aborted <<< camera_calibration_parsers [6.53s]
Aborted <<< gazebo_msgs [8.32s]

Summary: 0 packages finished [8.88s]
1 package failed: cv_bridge
5 packages aborted: camera_calibration_parsers gazebo_dev gazebo_msgs image_geometry image_transport
4 packages had stderr output: camera_calibration_parsers cv_bridge image_geometry image_transport
7 packages not processed