In the ACT, not only do kangaroos face the prospect of being killed by shooters each winter, they are also subject to fertility control by the ACT Government in the form of a contraceptive vaccine called GonaCon. This immunocontraceptive vaccine is used on female kangaroos and renders them infertile for as long as 8 years. Studies conducted showed that in female kangaroos treated by GonaCon, 80% of them were still infertile 5 years later. The ACT Government claims that the use of GonaCon will reduce the amount of killing needed in the future, however reality tells a different story.

Kangaroos living inside Mulligans Flat Woodland “Sanctuary” have been treated with GonaCon since 2022, however in 2025 they were subject to the biggest slaughter since 2019, with 176 kangaroos shot and 62 of their joeys killed. This calls into question the effectiveness of GonaCon at reducing the ACT Government’s perceived need for killing kangaroos.

Welfare of kangaroos treated by GonaCon
Key ACT Government ecologists working on the GonaCon program have stated that female kangaroos treated with GonaCon are “freed from the costs of reproduction”, resulting in outcomes such as increased survival and greater gain of body mass. Far from freedom, fertility control strips females of their bodily autonomy and prevents them from fulfilling their natural reproductive instincts. The psychological welfare impacts of this would be immeasurable.

Even more concerning, the behavioural effects from GonaCon have not been investigated in detail in female macropods by ACT Government ecologists. Given that females are the most likely to suffer psychological and physiological impacts from the fertility treatment, the fact that this has not been researched in more detail is very alarming.

Aside from the effects from the contraceptive itself, kangaroos treated with GonaCon are fitted with either large plastic collars and/or large plastic ear tags hole punched through both of their ears. Those with any knowledge of kangaroos would know that they have very sensitive ears and these ear tags would be causing significant discomfort. Members of SCK have sighted kangaroos with ear tags constantly scratching at their ears.

Are GonaCon treated kangaroos safe from shooters?
One would think that a kangaroo that had been treated with GonaCon would be offered some sort of protection during the ACT Government’s annual killing program and that shooters would avoid shooting those kangaroos that are clearly identifiable with the ear tags and/or collars. However, this is in fact not the case at all.

The shooter’s operational reports for 2025, obtained via FOI, revealed that two ear-tagged kangaroos were killed by ACT Government shooters. Presumably, this was not intentional as it would not make sense to be killing kangaroos who have been treated with Gonacon, because this would be a waste of ACT Government funding and it also doesn’t align with the purpose of the Gonacon program. Nevertheless it happened quite possibly due to shooter negligence.

This is indefensible. These kangaroos were subjected to invasive fertility control, only to be slaughtered anyway. 

More to come on this page soon…