Cairo Converts SVG to Black and White

Question

I am trying to convert an SVG into a PDF on the command line but both svg2pdf and cairosvg result in black and white images (the original is in colour).

$ identify original.svg
original.svg SVG 31x40 31x40+0+0 8-bit sRGB 1.11KB 0.010u 0:00.009
$ svg2pdf original.svg 1.pdf
$ identify 1.pdf
1.pdf PDF 450x450 450x450+0+0 16-bit Bilevel Gray 25.7KB 0.000u 0:00.009
$ cairosvg original.svg -o 2.pdf
$ identify 2.pdf
2.pdf PDF 23x30 23x30+0+0 16-bit Bilevel Gray 152B 0.000u 0:00.000

Neither utility has documentation on colour settings. Is there an argument to either utility or an alternative tool to convert SVGs to PDFs? It will need to be scripted.