The transport properties of a YBa$_2$Cu$_3$O$_{7-delta}$ superconducting quantum interference device (SQUID) based on grooved Dayem bridge weak links are studied as a function of temperature: at high temperatures ($60~$K$<T<T_mathrm{c}=89$~K) the weak links show properties similar to SNS junctions, while at temperatures below 60~K the weak links behave like short Dayem bridges. Using these devices, we have fabricated SQUID magnetometers with galvanically coupled in-plane pick-up loops: at $T=77$~K, magnetic field white noise levels as low as $63$~fT/$sqrt{mathrm{Hz}}$ have been achieved.
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